1 | divert(-1)# -*- Autoconf -*-
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2 | # This file is part of Autoconf.
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3 | # Base M4 layer.
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4 | # Requires GNU M4.
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5 | #
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6 | # Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
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7 | # 2008 Free Software Foundation, Inc.
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8 | #
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9 | # This program is free software: you can redistribute it and/or modify
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10 | # it under the terms of the GNU General Public License as published by
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11 | # the Free Software Foundation, either version 3 of the License, or
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12 | # (at your option) any later version.
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13 | #
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14 | # This program is distributed in the hope that it will be useful,
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15 | # but WITHOUT ANY WARRANTY; without even the implied warranty of
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16 | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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17 | # GNU General Public License for more details.
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18 | #
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19 | # You should have received a copy of the GNU General Public License
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20 | # along with this program. If not, see <http://www.gnu.org/licenses/>.
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21 |
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22 | # As a special exception, the Free Software Foundation gives unlimited
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23 | # permission to copy, distribute and modify the configure scripts that
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24 | # are the output of Autoconf. You need not follow the terms of the GNU
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25 | # General Public License when using or distributing such scripts, even
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26 | # though portions of the text of Autoconf appear in them. The GNU
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27 | # General Public License (GPL) does govern all other use of the material
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28 | # that constitutes the Autoconf program.
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29 | #
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30 | # Certain portions of the Autoconf source text are designed to be copied
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31 | # (in certain cases, depending on the input) into the output of
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32 | # Autoconf. We call these the "data" portions. The rest of the Autoconf
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33 | # source text consists of comments plus executable code that decides which
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34 | # of the data portions to output in any given case. We call these
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35 | # comments and executable code the "non-data" portions. Autoconf never
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36 | # copies any of the non-data portions into its output.
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37 | #
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38 | # This special exception to the GPL applies to versions of Autoconf
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39 | # released by the Free Software Foundation. When you make and
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40 | # distribute a modified version of Autoconf, you may extend this special
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41 | # exception to the GPL to apply to your modified version as well, *unless*
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42 | # your modified version has the potential to copy into its output some
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43 | # of the text that was the non-data portion of the version that you started
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44 | # with. (In other words, unless your change moves or copies text from
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45 | # the non-data portions to the data portions.) If your modification has
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46 | # such potential, you must delete any notice of this special exception
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47 | # to the GPL from your modified version.
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48 | #
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49 | # Written by Akim Demaille.
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50 | #
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51 |
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52 | # Set the quotes, whatever the current quoting system.
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53 | changequote()
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54 | changequote([, ])
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55 |
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56 | # Some old m4's don't support m4exit. But they provide
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57 | # equivalent functionality by core dumping because of the
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58 | # long macros we define.
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59 | ifdef([__gnu__], ,
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60 | [errprint(M4sugar requires GNU M4. Install it before installing M4sugar or
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61 | set the M4 environment variable to its absolute file name.)
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62 | m4exit(2)])
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63 |
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64 |
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65 | ## ------------------------------- ##
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66 | ## 1. Simulate --prefix-builtins. ##
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67 | ## ------------------------------- ##
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68 |
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69 | # m4_define
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70 | # m4_defn
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71 | # m4_undefine
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72 | define([m4_define], defn([define]))
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73 | define([m4_defn], defn([defn]))
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74 | define([m4_undefine], defn([undefine]))
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75 |
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76 | m4_undefine([define])
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77 | m4_undefine([defn])
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78 | m4_undefine([undefine])
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79 |
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80 |
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81 | # m4_copy(SRC, DST)
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82 | # -----------------
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83 | # Define DST as the definition of SRC.
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84 | # What's the difference between:
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85 | # 1. m4_copy([from], [to])
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86 | # 2. m4_define([to], [from($@)])
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87 | # Well, obviously 1 is more expensive in space. Maybe 2 is more expensive
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88 | # in time, but because of the space cost of 1, it's not that obvious.
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89 | # Nevertheless, one huge difference is the handling of `$0'. If `from'
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90 | # uses `$0', then with 1, `to''s `$0' is `to', while it is `from' in 2.
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91 | # The user would certainly prefer to see `to'.
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92 | m4_define([m4_copy],
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93 | [m4_define([$2], m4_defn([$1]))])
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94 |
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95 |
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96 | # m4_rename(SRC, DST)
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97 | # -------------------
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98 | # Rename the macro SRC to DST.
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99 | m4_define([m4_rename],
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100 | [m4_copy([$1], [$2])m4_undefine([$1])])
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101 |
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102 |
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103 | # m4_rename_m4(MACRO-NAME)
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104 | # ------------------------
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105 | # Rename MACRO-NAME to m4_MACRO-NAME.
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106 | m4_define([m4_rename_m4],
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107 | [m4_rename([$1], [m4_$1])])
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108 |
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109 |
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110 | # m4_copy_unm4(m4_MACRO-NAME)
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111 | # ---------------------------
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112 | # Copy m4_MACRO-NAME to MACRO-NAME.
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113 | m4_define([m4_copy_unm4],
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114 | [m4_copy([$1], m4_bpatsubst([$1], [^m4_\(.*\)], [[\1]]))])
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115 |
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116 |
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117 | # Some m4 internals have names colliding with tokens we might use.
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118 | # Rename them a` la `m4 --prefix-builtins'. Conditionals first, since
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119 | # some subsequent renames are conditional.
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120 | m4_rename_m4([ifdef])
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121 | m4_rename([ifelse], [m4_if])
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122 |
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123 | m4_rename_m4([builtin])
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124 | m4_rename_m4([changecom])
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125 | m4_rename_m4([changequote])
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126 | m4_ifdef([changeword],dnl conditionally available in 1.4.x
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127 | [m4_undefine([changeword])])
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128 | m4_rename_m4([debugfile])
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129 | m4_rename_m4([debugmode])
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130 | m4_rename_m4([decr])
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131 | m4_undefine([divert])
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132 | m4_rename_m4([divnum])
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133 | m4_rename_m4([dumpdef])
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134 | m4_rename_m4([errprint])
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135 | m4_rename_m4([esyscmd])
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136 | m4_rename_m4([eval])
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137 | m4_rename_m4([format])
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138 | m4_undefine([include])
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139 | m4_rename_m4([incr])
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140 | m4_rename_m4([index])
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141 | m4_rename_m4([indir])
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142 | m4_rename_m4([len])
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143 | m4_rename([m4exit], [m4_exit])
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144 | m4_undefine([m4wrap])
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145 | m4_ifdef([mkstemp],dnl added in M4 1.4.8
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146 | [m4_rename_m4([mkstemp])
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147 | m4_copy([m4_mkstemp], [m4_maketemp])
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148 | m4_undefine([maketemp])],
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149 | [m4_rename_m4([maketemp])
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150 | m4_copy([m4_maketemp], [m4_mkstemp])])
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151 | m4_rename([patsubst], [m4_bpatsubst])
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152 | m4_rename_m4([popdef])
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153 | m4_rename_m4([pushdef])
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154 | m4_rename([regexp], [m4_bregexp])
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155 | m4_rename_m4([shift])
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156 | m4_undefine([sinclude])
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157 | m4_rename_m4([substr])
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158 | m4_ifdef([symbols],dnl present only in alpha-quality 1.4o
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159 | [m4_rename_m4([symbols])])
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160 | m4_rename_m4([syscmd])
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161 | m4_rename_m4([sysval])
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162 | m4_rename_m4([traceoff])
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163 | m4_rename_m4([traceon])
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164 | m4_rename_m4([translit])
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165 | m4_undefine([undivert])
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166 |
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167 |
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168 | ## ------------------- ##
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169 | ## 2. Error messages. ##
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170 | ## ------------------- ##
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171 |
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172 |
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173 | # m4_location
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174 | # -----------
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175 | m4_define([m4_location],
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176 | [__file__:__line__])
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177 |
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178 |
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179 | # m4_errprintn(MSG)
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180 | # -----------------
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181 | # Same as `errprint', but with the missing end of line.
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182 | m4_define([m4_errprintn],
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183 | [m4_errprint([$1
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184 | ])])
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185 |
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186 |
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187 | # m4_warning(MSG)
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188 | # ---------------
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189 | # Warn the user.
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190 | m4_define([m4_warning],
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191 | [m4_errprintn(m4_location[: warning: $1])])
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192 |
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193 |
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194 | # m4_fatal(MSG, [EXIT-STATUS])
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195 | # ----------------------------
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196 | # Fatal the user. :)
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197 | m4_define([m4_fatal],
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198 | [m4_errprintn(m4_location[: error: $1])dnl
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199 | m4_expansion_stack_dump()dnl
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200 | m4_exit(m4_if([$2],, 1, [$2]))])
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201 |
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202 |
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203 | # m4_assert(EXPRESSION, [EXIT-STATUS = 1])
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204 | # ----------------------------------------
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205 | # This macro ensures that EXPRESSION evaluates to true, and exits if
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206 | # EXPRESSION evaluates to false.
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207 | m4_define([m4_assert],
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208 | [m4_if(m4_eval([$1]), 0,
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209 | [m4_fatal([assert failed: $1], [$2])])])
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210 |
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211 |
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212 |
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213 | ## ------------- ##
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214 | ## 3. Warnings. ##
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215 | ## ------------- ##
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216 |
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217 |
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218 | # _m4_warn(CATEGORY, MESSAGE, STACK-TRACE)
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219 | # ----------------------------------------
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220 | # Report a MESSAGE to the user if the CATEGORY of warnings is enabled.
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221 | # This is for traces only.
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222 | # The STACK-TRACE is a \n-separated list of "LOCATION: MESSAGE".
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223 | #
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224 | # Within m4, the macro is a no-op. This macro really matters
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225 | # when autom4te post-processes the trace output.
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226 | m4_define([_m4_warn], [])
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227 |
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228 |
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229 | # m4_warn(CATEGORY, MESSAGE)
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230 | # --------------------------
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231 | # Report a MESSAGE to the user if the CATEGORY of warnings is enabled.
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232 | m4_define([m4_warn],
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233 | [_m4_warn([$1], [$2],
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234 | m4_ifdef([m4_expansion_stack],
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235 | [_m4_defn([m4_expansion_stack])
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236 | m4_location[: the top level]]))dnl
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237 | ])
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238 |
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239 |
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240 |
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241 | ## ------------------- ##
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242 | ## 4. File inclusion. ##
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243 | ## ------------------- ##
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244 |
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245 |
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246 | # We also want to neutralize include (and sinclude for symmetry),
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247 | # but we want to extend them slightly: warn when a file is included
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248 | # several times. This is, in general, a dangerous operation, because
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249 | # too many people forget to quote the first argument of m4_define.
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250 | #
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251 | # For instance in the following case:
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252 | # m4_define(foo, [bar])
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253 | # then a second reading will turn into
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254 | # m4_define(bar, [bar])
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255 | # which is certainly not what was meant.
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256 |
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257 | # m4_include_unique(FILE)
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258 | # -----------------------
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259 | # Declare that the FILE was loading; and warn if it has already
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260 | # been included.
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261 | m4_define([m4_include_unique],
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262 | [m4_ifdef([m4_include($1)],
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263 | [m4_warn([syntax], [file `$1' included several times])])dnl
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264 | m4_define([m4_include($1)])])
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265 |
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266 |
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267 | # m4_include(FILE)
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268 | # ----------------
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269 | # Like the builtin include, but warns against multiple inclusions.
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270 | m4_define([m4_include],
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271 | [m4_include_unique([$1])dnl
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272 | m4_builtin([include], [$1])])
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273 |
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274 |
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275 | # m4_sinclude(FILE)
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276 | # -----------------
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277 | # Like the builtin sinclude, but warns against multiple inclusions.
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278 | m4_define([m4_sinclude],
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279 | [m4_include_unique([$1])dnl
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280 | m4_builtin([sinclude], [$1])])
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281 |
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282 |
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283 |
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284 | ## ------------------------------------ ##
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285 | ## 5. Additional branching constructs. ##
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286 | ## ------------------------------------ ##
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287 |
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288 | # Both `m4_ifval' and `m4_ifset' tests against the empty string. The
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289 | # difference is that `m4_ifset' is specialized on macros.
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290 | #
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291 | # In case of arguments of macros, eg. $1, it makes little difference.
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292 | # In the case of a macro `FOO', you don't want to check `m4_ifval(FOO,
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293 | # TRUE)', because if `FOO' expands with commas, there is a shifting of
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294 | # the arguments. So you want to run `m4_ifval([FOO])', but then you just
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295 | # compare the *string* `FOO' against `', which, of course fails.
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296 | #
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297 | # So you want the variation `m4_ifset' that expects a macro name as $1.
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298 | # If this macro is both defined and defined to a non empty value, then
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299 | # it runs TRUE, etc.
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300 |
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301 |
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302 | # m4_ifval(COND, [IF-TRUE], [IF-FALSE])
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303 | # -------------------------------------
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304 | # If COND is not the empty string, expand IF-TRUE, otherwise IF-FALSE.
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305 | # Comparable to m4_ifdef.
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306 | m4_define([m4_ifval],
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307 | [m4_if([$1], [], [$3], [$2])])
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308 |
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309 |
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310 | # m4_n(TEXT)
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311 | # ----------
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312 | # If TEXT is not empty, return TEXT and a new line, otherwise nothing.
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313 | m4_define([m4_n],
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314 | [m4_if([$1],
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315 | [], [],
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316 | [$1
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317 | ])])
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318 |
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319 |
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320 | # m4_ifvaln(COND, [IF-TRUE], [IF-FALSE])
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321 | # --------------------------------------
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322 | # Same as `m4_ifval', but add an extra newline to IF-TRUE or IF-FALSE
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323 | # unless that argument is empty.
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324 | m4_define([m4_ifvaln],
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325 | [m4_if([$1],
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326 | [], [m4_n([$3])],
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327 | [m4_n([$2])])])
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328 |
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329 |
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330 | # m4_ifset(MACRO, [IF-TRUE], [IF-FALSE])
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331 | # --------------------------------------
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332 | # If MACRO has no definition, or of its definition is the empty string,
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333 | # expand IF-FALSE, otherwise IF-TRUE.
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334 | m4_define([m4_ifset],
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335 | [m4_ifdef([$1],
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336 | [m4_ifval(_m4_defn([$1]), [$2], [$3])],
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337 | [$3])])
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338 |
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339 |
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340 | # m4_ifndef(NAME, [IF-NOT-DEFINED], [IF-DEFINED])
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341 | # -----------------------------------------------
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342 | m4_define([m4_ifndef],
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343 | [m4_ifdef([$1], [$3], [$2])])
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344 |
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345 |
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346 | # m4_case(SWITCH, VAL1, IF-VAL1, VAL2, IF-VAL2, ..., DEFAULT)
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347 | # -----------------------------------------------------------
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348 | # m4 equivalent of
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349 | # switch (SWITCH)
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350 | # {
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351 | # case VAL1:
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352 | # IF-VAL1;
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353 | # break;
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354 | # case VAL2:
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355 | # IF-VAL2;
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356 | # break;
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357 | # ...
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358 | # default:
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359 | # DEFAULT;
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360 | # break;
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361 | # }.
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362 | # All the values are optional, and the macro is robust to active
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363 | # symbols properly quoted.
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364 | #
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365 | # Please keep foreach.m4 in sync with any adjustments made here.
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366 | m4_define([m4_case],
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367 | [m4_if([$#], 0, [],
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368 | [$#], 1, [],
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369 | [$#], 2, [$2],
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370 | [$1], [$2], [$3],
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371 | [$0([$1], m4_shift3($@))])])
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372 |
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373 |
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374 | # m4_bmatch(SWITCH, RE1, VAL1, RE2, VAL2, ..., DEFAULT)
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375 | # -----------------------------------------------------
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376 | # m4 equivalent of
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377 | #
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378 | # if (SWITCH =~ RE1)
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379 | # VAL1;
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380 | # elif (SWITCH =~ RE2)
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381 | # VAL2;
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382 | # elif ...
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383 | # ...
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384 | # else
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385 | # DEFAULT
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386 | #
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387 | # All the values are optional, and the macro is robust to active symbols
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388 | # properly quoted.
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389 | #
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390 | # Please keep foreach.m4 in sync with any adjustments made here.
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391 | m4_define([m4_bmatch],
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392 | [m4_if([$#], 0, [m4_fatal([$0: too few arguments: $#])],
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393 | [$#], 1, [m4_fatal([$0: too few arguments: $#: $1])],
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394 | [$#], 2, [$2],
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395 | [m4_if(m4_bregexp([$1], [$2]), -1, [$0([$1], m4_shift3($@))],
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396 | [$3])])])
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397 |
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398 |
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399 | # m4_car(LIST)
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400 | # m4_cdr(LIST)
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401 | # ------------
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402 | # Manipulate m4 lists.
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403 | m4_define([m4_car], [[$1]])
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404 | m4_define([m4_cdr],
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405 | [m4_if([$#], 0, [m4_fatal([$0: cannot be called without arguments])],
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406 | [$#], 1, [],
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407 | [m4_dquote(m4_shift($@))])])
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408 |
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409 | # _m4_cdr(LIST)
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410 | # -------------
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411 | # Like m4_cdr, except include a leading comma unless only one element
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412 | # remains. Why? Because comparing a large list against [] is more
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413 | # expensive in expansion time than comparing the number of arguments; so
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414 | # _m4_cdr can be used to reduce the number of arguments when it is time
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415 | # to end recursion.
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416 | m4_define([_m4_cdr],
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417 | [m4_if([$#], 1, [],
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418 | [, m4_dquote(m4_shift($@))])])
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419 |
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420 |
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421 |
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422 | # m4_cond(TEST1, VAL1, IF-VAL1, TEST2, VAL2, IF-VAL2, ..., [DEFAULT])
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423 | # -------------------------------------------------------------------
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424 | # Similar to m4_if, except that each TEST is expanded when encountered.
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425 | # If the expansion of TESTn matches the string VALn, the result is IF-VALn.
|
---|
426 | # The result is DEFAULT if no tests passed. This macro allows
|
---|
427 | # short-circuiting of expensive tests, where it pays to arrange quick
|
---|
428 | # filter tests to run first.
|
---|
429 | #
|
---|
430 | # For an example, consider a previous implementation of _AS_QUOTE_IFELSE:
|
---|
431 | #
|
---|
432 | # m4_if(m4_index([$1], [\]), [-1], [$2],
|
---|
433 | # m4_eval(m4_index([$1], [\\]) >= 0), [1], [$2],
|
---|
434 | # m4_eval(m4_index([$1], [\$]) >= 0), [1], [$2],
|
---|
435 | # m4_eval(m4_index([$1], [\`]) >= 0), [1], [$3],
|
---|
436 | # m4_eval(m4_index([$1], [\"]) >= 0), [1], [$3],
|
---|
437 | # [$2])
|
---|
438 | #
|
---|
439 | # Here, m4_index is computed 5 times, and m4_eval 4, even if $1 contains
|
---|
440 | # no backslash. It is more efficient to do:
|
---|
441 | #
|
---|
442 | # m4_cond([m4_index([$1], [\])], [-1], [$2],
|
---|
443 | # [m4_eval(m4_index([$1], [\\]) >= 0)], [1], [$2],
|
---|
444 | # [m4_eval(m4_index([$1], [\$]) >= 0)], [1], [$2],
|
---|
445 | # [m4_eval(m4_index([$1], [\`]) >= 0)], [1], [$3],
|
---|
446 | # [m4_eval(m4_index([$1], [\"]) >= 0)], [1], [$3],
|
---|
447 | # [$2])
|
---|
448 | #
|
---|
449 | # In the common case of $1 with no backslash, only one m4_index expansion
|
---|
450 | # occurs, and m4_eval is avoided altogether.
|
---|
451 | #
|
---|
452 | # Please keep foreach.m4 in sync with any adjustments made here.
|
---|
453 | m4_define([m4_cond],
|
---|
454 | [m4_if([$#], [0], [m4_fatal([$0: cannot be called without arguments])],
|
---|
455 | [$#], [1], [$1],
|
---|
456 | m4_eval([$# % 3]), [2], [m4_fatal([$0: missing an argument])],
|
---|
457 | [_$0($@)])])
|
---|
458 |
|
---|
459 | m4_define([_m4_cond],
|
---|
460 | [m4_if(($1), [($2)], [$3],
|
---|
461 | [$#], [3], [],
|
---|
462 | [$#], [4], [$4],
|
---|
463 | [$0(m4_shift3($@))])])
|
---|
464 |
|
---|
465 |
|
---|
466 | ## ---------------------------------------- ##
|
---|
467 | ## 6. Enhanced version of some primitives. ##
|
---|
468 | ## ---------------------------------------- ##
|
---|
469 |
|
---|
470 | # m4_bpatsubsts(STRING, RE1, SUBST1, RE2, SUBST2, ...)
|
---|
471 | # ----------------------------------------------------
|
---|
472 | # m4 equivalent of
|
---|
473 | #
|
---|
474 | # $_ = STRING;
|
---|
475 | # s/RE1/SUBST1/g;
|
---|
476 | # s/RE2/SUBST2/g;
|
---|
477 | # ...
|
---|
478 | #
|
---|
479 | # All the values are optional, and the macro is robust to active symbols
|
---|
480 | # properly quoted.
|
---|
481 | #
|
---|
482 | # I would have liked to name this macro `m4_bpatsubst', unfortunately,
|
---|
483 | # due to quotation problems, I need to double quote $1 below, therefore
|
---|
484 | # the anchors are broken :( I can't let users be trapped by that.
|
---|
485 | #
|
---|
486 | # Recall that m4_shift3 always results in an argument. Hence, we need
|
---|
487 | # to distinguish between a final deletion vs. ending recursion.
|
---|
488 | #
|
---|
489 | # Please keep foreach.m4 in sync with any adjustments made here.
|
---|
490 | m4_define([m4_bpatsubsts],
|
---|
491 | [m4_if([$#], 0, [m4_fatal([$0: too few arguments: $#])],
|
---|
492 | [$#], 1, [m4_fatal([$0: too few arguments: $#: $1])],
|
---|
493 | [$#], 2, [m4_unquote(m4_builtin([patsubst], [[$1]], [$2]))],
|
---|
494 | [$#], 3, [m4_unquote(m4_builtin([patsubst], [[$1]], [$2], [$3]))],
|
---|
495 | [_$0($@m4_if(m4_eval($# & 1), 0, [,]))])])
|
---|
496 | m4_define([_m4_bpatsubsts],
|
---|
497 | [m4_if([$#], 2, [$1],
|
---|
498 | [$0(m4_builtin([patsubst], [[$1]], [$2], [$3]),
|
---|
499 | m4_shift3($@))])])
|
---|
500 |
|
---|
501 |
|
---|
502 | # m4_define_default(MACRO, VALUE)
|
---|
503 | # -------------------------------
|
---|
504 | # If MACRO is undefined, set it to VALUE.
|
---|
505 | m4_define([m4_define_default],
|
---|
506 | [m4_ifndef([$1], [m4_define($@)])])
|
---|
507 |
|
---|
508 |
|
---|
509 | # m4_default(EXP1, EXP2)
|
---|
510 | # ----------------------
|
---|
511 | # Returns EXP1 if non empty, otherwise EXP2.
|
---|
512 | #
|
---|
513 | # This macro is called on hot paths, so inline the contents of m4_ifval,
|
---|
514 | # for one less round of expansion.
|
---|
515 | m4_define([m4_default],
|
---|
516 | [m4_if([$1], [], [$2], [$1])])
|
---|
517 |
|
---|
518 |
|
---|
519 | # m4_defn(NAME)
|
---|
520 | # -------------
|
---|
521 | # Like the original, except guarantee a warning when using something which is
|
---|
522 | # undefined (unlike M4 1.4.x). This replacement is not a full-featured
|
---|
523 | # replacement: if any of the defined macros contain unbalanced quoting, but
|
---|
524 | # when pasted together result in a well-quoted string, then only native m4
|
---|
525 | # support is able to get it correct. But that's where quadrigraphs come in
|
---|
526 | # handy, if you really need unbalanced quotes inside your macros.
|
---|
527 | #
|
---|
528 | # This macro is called frequently, so minimize the amount of additional
|
---|
529 | # expansions by skipping m4_ifndef. Better yet, if __m4_version__ exists,
|
---|
530 | # (added in M4 1.6), then let m4 do the job for us (see m4_init).
|
---|
531 | #
|
---|
532 | # _m4_defn is for internal use only - it bypasses the wrapper, so it
|
---|
533 | # must only be used on one argument at a time, and only on macros
|
---|
534 | # known to be defined. Make sure this still works if the user renames
|
---|
535 | # m4_defn but not _m4_defn.
|
---|
536 | m4_copy([m4_defn], [_m4_defn])
|
---|
537 | m4_define([m4_defn],
|
---|
538 | [m4_if([$#], [0], [[$0]],
|
---|
539 | [$#], [1], [m4_ifdef([$1], [_m4_defn([$1])],
|
---|
540 | [m4_fatal([$0: undefined macro: $1])])],
|
---|
541 | [m4_foreach([_m4_macro], [$@], [$0(_m4_defn([_m4_macro]))])])])
|
---|
542 |
|
---|
543 |
|
---|
544 | # _m4_dumpdefs_up(NAME)
|
---|
545 | # ---------------------
|
---|
546 | m4_define([_m4_dumpdefs_up],
|
---|
547 | [m4_ifdef([$1],
|
---|
548 | [m4_pushdef([_m4_dumpdefs], _m4_defn([$1]))dnl
|
---|
549 | m4_dumpdef([$1])dnl
|
---|
550 | _m4_popdef([$1])dnl
|
---|
551 | _m4_dumpdefs_up([$1])])])
|
---|
552 |
|
---|
553 |
|
---|
554 | # _m4_dumpdefs_down(NAME)
|
---|
555 | # -----------------------
|
---|
556 | m4_define([_m4_dumpdefs_down],
|
---|
557 | [m4_ifdef([_m4_dumpdefs],
|
---|
558 | [m4_pushdef([$1], _m4_defn([_m4_dumpdefs]))dnl
|
---|
559 | _m4_popdef([_m4_dumpdefs])dnl
|
---|
560 | _m4_dumpdefs_down([$1])])])
|
---|
561 |
|
---|
562 |
|
---|
563 | # m4_dumpdefs(NAME)
|
---|
564 | # -----------------
|
---|
565 | # Similar to `m4_dumpdef(NAME)', but if NAME was m4_pushdef'ed, display its
|
---|
566 | # value stack (most recent displayed first).
|
---|
567 | m4_define([m4_dumpdefs],
|
---|
568 | [_m4_dumpdefs_up([$1])dnl
|
---|
569 | _m4_dumpdefs_down([$1])])
|
---|
570 |
|
---|
571 |
|
---|
572 | # m4_popdef(NAME)
|
---|
573 | # ---------------
|
---|
574 | # Like the original, except guarantee a warning when using something which is
|
---|
575 | # undefined (unlike M4 1.4.x).
|
---|
576 | #
|
---|
577 | # This macro is called frequently, so minimize the amount of additional
|
---|
578 | # expansions by skipping m4_ifndef. Better yet, if __m4_version__ exists,
|
---|
579 | # (added in M4 1.6), then let m4 do the job for us (see m4_init).
|
---|
580 | #
|
---|
581 | # _m4_popdef is for internal use only - it bypasses the wrapper, so it
|
---|
582 | # must only be used on macros known to be defined. Make sure this
|
---|
583 | # still works if the user renames m4_popdef but not _m4_popdef.
|
---|
584 | m4_copy([m4_popdef], [_m4_popdef])
|
---|
585 | m4_define([m4_popdef],
|
---|
586 | [m4_if([$#], [0], [[$0]],
|
---|
587 | [$#], [1], [m4_ifdef([$1], [_m4_popdef([$1])],
|
---|
588 | [m4_fatal([$0: undefined macro: $1])])],
|
---|
589 | [m4_foreach([_m4_macro], [$@], [$0(_m4_defn([_m4_macro]))])])])
|
---|
590 |
|
---|
591 |
|
---|
592 | # m4_shiftn(N, ...)
|
---|
593 | # -----------------
|
---|
594 | # Returns ... shifted N times. Useful for recursive "varargs" constructs.
|
---|
595 | #
|
---|
596 | # Autoconf does not use this macro, because it is inherently slower than
|
---|
597 | # calling the common cases of m4_shift2 or m4_shift3 directly. But it
|
---|
598 | # might as well be fast for other clients, such as Libtool. One way to
|
---|
599 | # do this is to expand $@ only once in _m4_shiftn (otherwise, for long
|
---|
600 | # lists, the expansion of m4_if takes twice as much memory as what the
|
---|
601 | # list itself occupies, only to throw away the unused branch). The end
|
---|
602 | # result is strictly equivalent to
|
---|
603 | # m4_if([$1], 1, [m4_shift(,m4_shift(m4_shift($@)))],
|
---|
604 | # [_m4_shiftn(m4_decr([$1]), m4_shift(m4_shift($@)))])
|
---|
605 | # but with the final `m4_shift(m4_shift($@)))' shared between the two
|
---|
606 | # paths. The first leg uses a no-op m4_shift(,$@) to balance out the ().
|
---|
607 | #
|
---|
608 | # Please keep foreach.m4 in sync with any adjustments made here.
|
---|
609 | m4_define([m4_shiftn],
|
---|
610 | [m4_assert(0 < $1 && $1 < $#)_$0($@)])
|
---|
611 |
|
---|
612 | m4_define([_m4_shiftn],
|
---|
613 | [m4_if([$1], 1, [m4_shift(],
|
---|
614 | [$0(m4_decr([$1])]), m4_shift(m4_shift($@)))])
|
---|
615 |
|
---|
616 | # m4_shift2(...)
|
---|
617 | # m4_shift3(...)
|
---|
618 | # -----------------
|
---|
619 | # Returns ... shifted twice, and three times. Faster than m4_shiftn.
|
---|
620 | m4_define([m4_shift2], [m4_shift(m4_shift($@))])
|
---|
621 | m4_define([m4_shift3], [m4_shift(m4_shift(m4_shift($@)))])
|
---|
622 |
|
---|
623 | # _m4_shift2(...)
|
---|
624 | # _m4_shift3(...)
|
---|
625 | # ---------------
|
---|
626 | # Like m4_shift2 or m4_shift3, except include a leading comma unless shifting
|
---|
627 | # consumes all arguments. Why? Because in recursion, it is nice to
|
---|
628 | # distinguish between 1 element left and 0 elements left, based on how many
|
---|
629 | # arguments this shift expands to.
|
---|
630 | m4_define([_m4_shift2],
|
---|
631 | [m4_if([$#], [2], [],
|
---|
632 | [, m4_shift(m4_shift($@))])])
|
---|
633 | m4_define([_m4_shift3],
|
---|
634 | [m4_if([$#], [3], [],
|
---|
635 | [, m4_shift(m4_shift(m4_shift($@)))])])
|
---|
636 |
|
---|
637 |
|
---|
638 | # m4_undefine(NAME)
|
---|
639 | # -----------------
|
---|
640 | # Like the original, except guarantee a warning when using something which is
|
---|
641 | # undefined (unlike M4 1.4.x).
|
---|
642 | #
|
---|
643 | # This macro is called frequently, so minimize the amount of additional
|
---|
644 | # expansions by skipping m4_ifndef. Better yet, if __m4_version__ exists,
|
---|
645 | # (added in M4 1.6), then let m4 do the job for us (see m4_init).
|
---|
646 | #
|
---|
647 | # _m4_undefine is for internal use only - it bypasses the wrapper, so
|
---|
648 | # it must only be used on macros known to be defined. Make sure this
|
---|
649 | # still works if the user renames m4_undefine but not _m4_undefine.
|
---|
650 | m4_copy([m4_undefine], [_m4_undefine])
|
---|
651 | m4_define([m4_undefine],
|
---|
652 | [m4_if([$#], [0], [[$0]],
|
---|
653 | [$#], [1], [m4_ifdef([$1], [_m4_undefine([$1])],
|
---|
654 | [m4_fatal([$0: undefined macro: $1])])],
|
---|
655 | [m4_foreach([_m4_macro], [$@], [$0(_m4_defn([_m4_macro]))])])])
|
---|
656 |
|
---|
657 | # _m4_wrap(PRE, POST)
|
---|
658 | # -------------------
|
---|
659 | # Helper macro for m4_wrap and m4_wrap_lifo. Allows nested calls to
|
---|
660 | # m4_wrap within wrapped text. Use _m4_defn and _m4_popdef for speed.
|
---|
661 | m4_define([_m4_wrap],
|
---|
662 | [m4_ifdef([$0_text],
|
---|
663 | [m4_define([$0_text], [$1]_m4_defn([$0_text])[$2])],
|
---|
664 | [m4_builtin([m4wrap], [m4_unquote(
|
---|
665 | _m4_defn([$0_text])_m4_popdef([$0_text]))])m4_define([$0_text], [$1$2])])])
|
---|
666 |
|
---|
667 | # m4_wrap(TEXT)
|
---|
668 | # -------------
|
---|
669 | # Append TEXT to the list of hooks to be executed at the end of input.
|
---|
670 | # Whereas the order of the original may be LIFO in the underlying m4,
|
---|
671 | # this version is always FIFO.
|
---|
672 | m4_define([m4_wrap],
|
---|
673 | [_m4_wrap([], [$1[]])])
|
---|
674 |
|
---|
675 | # m4_wrap_lifo(TEXT)
|
---|
676 | # ------------------
|
---|
677 | # Prepend TEXT to the list of hooks to be executed at the end of input.
|
---|
678 | # Whereas the order of m4_wrap may be FIFO in the underlying m4, this
|
---|
679 | # version is always LIFO.
|
---|
680 | m4_define([m4_wrap_lifo],
|
---|
681 | [_m4_wrap([$1[]])])
|
---|
682 |
|
---|
683 | ## ------------------------- ##
|
---|
684 | ## 7. Quoting manipulation. ##
|
---|
685 | ## ------------------------- ##
|
---|
686 |
|
---|
687 |
|
---|
688 | # m4_apply(MACRO, LIST)
|
---|
689 | # ---------------------
|
---|
690 | # Invoke MACRO, with arguments provided from the quoted list of
|
---|
691 | # comma-separated quoted arguments. If LIST is empty, invoke MACRO
|
---|
692 | # without arguments. The expansion will not be concatenated with
|
---|
693 | # subsequent text.
|
---|
694 | m4_define([m4_apply],
|
---|
695 | [m4_if([$2], [], [$1], [$1($2)])[]])
|
---|
696 |
|
---|
697 | # _m4_apply(MACRO, LIST)
|
---|
698 | # ----------------------
|
---|
699 | # Like m4_apply, except do nothing if LIST is empty.
|
---|
700 | m4_define([_m4_apply],
|
---|
701 | [m4_if([$2], [], [], [$1($2)[]])])
|
---|
702 |
|
---|
703 |
|
---|
704 | # m4_count(ARGS)
|
---|
705 | # --------------
|
---|
706 | # Return a count of how many ARGS are present.
|
---|
707 | m4_define([m4_count], [$#])
|
---|
708 |
|
---|
709 |
|
---|
710 | # m4_do(STRING, ...)
|
---|
711 | # ------------------
|
---|
712 | # This macro invokes all its arguments (in sequence, of course). It is
|
---|
713 | # useful for making your macros more structured and readable by dropping
|
---|
714 | # unnecessary dnl's and have the macros indented properly. No concatenation
|
---|
715 | # occurs after a STRING; use m4_unquote(m4_join(,STRING)) for that.
|
---|
716 | #
|
---|
717 | # Please keep foreach.m4 in sync with any adjustments made here.
|
---|
718 | m4_define([m4_do],
|
---|
719 | [m4_if([$#], 0, [],
|
---|
720 | [$#], 1, [$1[]],
|
---|
721 | [$1[]$0(m4_shift($@))])])
|
---|
722 |
|
---|
723 |
|
---|
724 | # m4_dquote(ARGS)
|
---|
725 | # ---------------
|
---|
726 | # Return ARGS as a quoted list of quoted arguments.
|
---|
727 | m4_define([m4_dquote], [[$@]])
|
---|
728 |
|
---|
729 |
|
---|
730 | # m4_dquote_elt(ARGS)
|
---|
731 | # -------------------
|
---|
732 | # Return ARGS as an unquoted list of double-quoted arguments.
|
---|
733 | #
|
---|
734 | # Please keep foreach.m4 in sync with any adjustments made here.
|
---|
735 | m4_define([m4_dquote_elt],
|
---|
736 | [m4_if([$#], [0], [],
|
---|
737 | [$#], [1], [[[$1]]],
|
---|
738 | [[[$1]],$0(m4_shift($@))])])
|
---|
739 |
|
---|
740 |
|
---|
741 | # m4_echo(ARGS)
|
---|
742 | # -------------
|
---|
743 | # Return the ARGS, with the same level of quoting. Whitespace after
|
---|
744 | # unquoted commas are consumed.
|
---|
745 | m4_define([m4_echo], [$@])
|
---|
746 |
|
---|
747 |
|
---|
748 | # m4_expand(ARG)
|
---|
749 | # --------------
|
---|
750 | # Return the expansion of ARG as a single string. Unlike m4_quote($1), this
|
---|
751 | # correctly preserves whitespace following single-quoted commas that appeared
|
---|
752 | # within ARG.
|
---|
753 | #
|
---|
754 | # m4_define([active], [ACT, IVE])
|
---|
755 | # m4_define([active2], [[ACT, IVE]])
|
---|
756 | # m4_quote(active, active2)
|
---|
757 | # => ACT,IVE,ACT, IVE
|
---|
758 | # m4_expand([active, active2])
|
---|
759 | # => ACT, IVE, ACT, IVE
|
---|
760 | #
|
---|
761 | # Unfortunately, due to limitations in m4, ARG must expand to something
|
---|
762 | # with balanced quotes (use quadrigraphs to get around this). The input
|
---|
763 | # is not likely to have unbalanced -=<{(/)}>=- quotes, and it is possible
|
---|
764 | # to have unbalanced (), provided it was specified with proper [] quotes.
|
---|
765 | #
|
---|
766 | # Exploit that extra () will group unquoted commas and the following
|
---|
767 | # whitespace, then convert () to []. m4_bpatsubst can't handle newlines
|
---|
768 | # inside $1, and m4_substr strips quoting. So we (ab)use m4_changequote.
|
---|
769 | m4_define([m4_expand], [_$0(-=<{($1)}>=-)])
|
---|
770 | m4_define([_m4_expand],
|
---|
771 | [m4_changequote([-=<{(], [)}>=-])$1m4_changequote([, ])])
|
---|
772 |
|
---|
773 |
|
---|
774 | # m4_ignore(ARGS)
|
---|
775 | # ---------------
|
---|
776 | # Expands to nothing. Useful for conditionally ignoring an arbitrary
|
---|
777 | # number of arguments (see _m4_list_cmp for an example).
|
---|
778 | m4_define([m4_ignore])
|
---|
779 |
|
---|
780 |
|
---|
781 | # m4_make_list(ARGS)
|
---|
782 | # ------------------
|
---|
783 | # Similar to m4_dquote, this creates a quoted list of quoted ARGS. This
|
---|
784 | # version is less efficient than m4_dquote, but separates each argument
|
---|
785 | # with a comma and newline, rather than just comma, for readability.
|
---|
786 | # When developing an m4sugar algorithm, you could temporarily use
|
---|
787 | # m4_pushdef([m4_dquote],m4_defn([m4_make_list]))
|
---|
788 | # around your code to make debugging easier.
|
---|
789 | m4_define([m4_make_list], [m4_join([,
|
---|
790 | ], m4_dquote_elt($@))])
|
---|
791 |
|
---|
792 |
|
---|
793 | # m4_noquote(STRING)
|
---|
794 | # ------------------
|
---|
795 | # Return the result of ignoring all quotes in STRING and invoking the
|
---|
796 | # macros it contains. Amongst other things, this is useful for enabling
|
---|
797 | # macro invocations inside strings with [] blocks (for instance regexps
|
---|
798 | # and help-strings). On the other hand, since all quotes are disabled,
|
---|
799 | # any macro expanded during this time that relies on nested [] quoting
|
---|
800 | # will likely crash and burn. This macro is seldom useful; consider
|
---|
801 | # m4_unquote or m4_expand instead.
|
---|
802 | m4_define([m4_noquote],
|
---|
803 | [m4_changequote([-=<{(],[)}>=-])$1-=<{()}>=-m4_changequote([,])])
|
---|
804 |
|
---|
805 |
|
---|
806 | # m4_quote(ARGS)
|
---|
807 | # --------------
|
---|
808 | # Return ARGS as a single argument. Any whitespace after unquoted commas
|
---|
809 | # is stripped. There is always output, even when there were no arguments.
|
---|
810 | #
|
---|
811 | # It is important to realize the difference between `m4_quote(exp)' and
|
---|
812 | # `[exp]': in the first case you obtain the quoted *result* of the
|
---|
813 | # expansion of EXP, while in the latter you just obtain the string
|
---|
814 | # `exp'.
|
---|
815 | m4_define([m4_quote], [[$*]])
|
---|
816 |
|
---|
817 |
|
---|
818 | # _m4_quote(ARGS)
|
---|
819 | # ---------------
|
---|
820 | # Like m4_quote, except that when there are no arguments, there is no
|
---|
821 | # output. For conditional scenarios (such as passing _m4_quote as the
|
---|
822 | # macro name in m4_mapall), this feature can be used to distinguish between
|
---|
823 | # one argument of the empty string vs. no arguments. However, in the
|
---|
824 | # normal case with arguments present, this is less efficient than m4_quote.
|
---|
825 | m4_define([_m4_quote],
|
---|
826 | [m4_if([$#], [0], [], [[$*]])])
|
---|
827 |
|
---|
828 |
|
---|
829 | # m4_reverse(ARGS)
|
---|
830 | # ----------------
|
---|
831 | # Output ARGS in reverse order.
|
---|
832 | #
|
---|
833 | # Please keep foreach.m4 in sync with any adjustments made here.
|
---|
834 | m4_define([m4_reverse],
|
---|
835 | [m4_if([$#], [0], [], [$#], [1], [[$1]],
|
---|
836 | [$0(m4_shift($@)), [$1]])])
|
---|
837 |
|
---|
838 |
|
---|
839 | # m4_unquote(ARGS)
|
---|
840 | # ----------------
|
---|
841 | # Remove one layer of quotes from each ARG, performing one level of
|
---|
842 | # expansion. For one argument, m4_unquote([arg]) is more efficient than
|
---|
843 | # m4_do([arg]), but for multiple arguments, the difference is that
|
---|
844 | # m4_unquote separates arguments with commas while m4_do concatenates.
|
---|
845 | # Follow this macro with [] if concatenation with subsequent text is
|
---|
846 | # undesired.
|
---|
847 | m4_define([m4_unquote], [$*])
|
---|
848 |
|
---|
849 |
|
---|
850 | ## -------------------------- ##
|
---|
851 | ## 8. Implementing m4 loops. ##
|
---|
852 | ## -------------------------- ##
|
---|
853 |
|
---|
854 |
|
---|
855 | # m4_for(VARIABLE, FIRST, LAST, [STEP = +/-1], EXPRESSION)
|
---|
856 | # --------------------------------------------------------
|
---|
857 | # Expand EXPRESSION defining VARIABLE to FROM, FROM + 1, ..., TO with
|
---|
858 | # increments of STEP. Both limits are included, and bounds are
|
---|
859 | # checked for consistency. The algorithm is robust to indirect
|
---|
860 | # VARIABLE names. Changing VARIABLE inside EXPRESSION will not impact
|
---|
861 | # the number of iterations.
|
---|
862 | #
|
---|
863 | # Uses _m4_defn for speed, and avoid dnl in the macro body.
|
---|
864 | m4_define([m4_for],
|
---|
865 | [m4_pushdef([$1], m4_eval([$2]))]dnl
|
---|
866 | [m4_cond([m4_eval(([$3]) > ([$2]))], 1,
|
---|
867 | [m4_pushdef([_m4_step], m4_eval(m4_default([$4],
|
---|
868 | 1)))m4_assert(_m4_step > 0)_$0([$1], _m4_defn([$1]),
|
---|
869 | m4_eval((([$3]) - ([$2])) / _m4_step * _m4_step + ([$2])),
|
---|
870 | _m4_step, [$5])],
|
---|
871 | [m4_eval(([$3]) < ([$2]))], 1,
|
---|
872 | [m4_pushdef([_m4_step], m4_eval(m4_default([$4],
|
---|
873 | -1)))m4_assert(_m4_step < 0)_$0([$1], _m4_defn([$1]),
|
---|
874 | m4_eval((([$2]) - ([$3])) / -(_m4_step) * _m4_step + ([$2])),
|
---|
875 | _m4_step, [$5])],
|
---|
876 | [m4_pushdef([_m4_step])$5])[]]dnl
|
---|
877 | [m4_popdef([_m4_step], [$1])])
|
---|
878 |
|
---|
879 |
|
---|
880 | # _m4_for(VARIABLE, COUNT, LAST, STEP, EXPRESSION)
|
---|
881 | # ------------------------------------------------
|
---|
882 | # Core of the loop, no consistency checks, all arguments are plain
|
---|
883 | # numbers. Define VARIABLE to COUNT, expand EXPRESSION, then alter
|
---|
884 | # COUNT by STEP and iterate if COUNT is not LAST.
|
---|
885 | m4_define([_m4_for],
|
---|
886 | [m4_define([$1], [$2])$5[]m4_if([$2], [$3], [],
|
---|
887 | [$0([$1], m4_eval([$2 + $4]), [$3], [$4], [$5])])])
|
---|
888 |
|
---|
889 |
|
---|
890 | # Implementing `foreach' loops in m4 is much more tricky than it may
|
---|
891 | # seem. For example, the old M4 1.4.4 manual had an incorrect example,
|
---|
892 | # which looked like this (when translated to m4sugar):
|
---|
893 | #
|
---|
894 | # | # foreach(VAR, (LIST), STMT)
|
---|
895 | # | m4_define([foreach],
|
---|
896 | # | [m4_pushdef([$1])_foreach([$1], [$2], [$3])m4_popdef([$1])])
|
---|
897 | # | m4_define([_arg1], [$1])
|
---|
898 | # | m4_define([_foreach],
|
---|
899 | # | [m4_if([$2], [()], ,
|
---|
900 | # | [m4_define([$1], _arg1$2)$3[]_foreach([$1], (m4_shift$2), [$3])])])
|
---|
901 | #
|
---|
902 | # But then if you run
|
---|
903 | #
|
---|
904 | # | m4_define(a, 1)
|
---|
905 | # | m4_define(b, 2)
|
---|
906 | # | m4_define(c, 3)
|
---|
907 | # | foreach([f], [([a], [(b], [c)])], [echo f
|
---|
908 | # | ])
|
---|
909 | #
|
---|
910 | # it gives
|
---|
911 | #
|
---|
912 | # => echo 1
|
---|
913 | # => echo (2,3)
|
---|
914 | #
|
---|
915 | # which is not what is expected.
|
---|
916 | #
|
---|
917 | # Of course the problem is that many quotes are missing. So you add
|
---|
918 | # plenty of quotes at random places, until you reach the expected
|
---|
919 | # result. Alternatively, if you are a quoting wizard, you directly
|
---|
920 | # reach the following implementation (but if you really did, then
|
---|
921 | # apply to the maintenance of m4sugar!).
|
---|
922 | #
|
---|
923 | # | # foreach(VAR, (LIST), STMT)
|
---|
924 | # | m4_define([foreach], [m4_pushdef([$1])_foreach($@)m4_popdef([$1])])
|
---|
925 | # | m4_define([_arg1], [[$1]])
|
---|
926 | # | m4_define([_foreach],
|
---|
927 | # | [m4_if($2, [()], ,
|
---|
928 | # | [m4_define([$1], [_arg1$2])$3[]_foreach([$1], [(m4_shift$2)], [$3])])])
|
---|
929 | #
|
---|
930 | # which this time answers
|
---|
931 | #
|
---|
932 | # => echo a
|
---|
933 | # => echo (b
|
---|
934 | # => echo c)
|
---|
935 | #
|
---|
936 | # Bingo!
|
---|
937 | #
|
---|
938 | # Well, not quite.
|
---|
939 | #
|
---|
940 | # With a better look, you realize that the parens are more a pain than
|
---|
941 | # a help: since anyway you need to quote properly the list, you end up
|
---|
942 | # with always using an outermost pair of parens and an outermost pair
|
---|
943 | # of quotes. Rejecting the parens both eases the implementation, and
|
---|
944 | # simplifies the use:
|
---|
945 | #
|
---|
946 | # | # foreach(VAR, (LIST), STMT)
|
---|
947 | # | m4_define([foreach], [m4_pushdef([$1])_foreach($@)m4_popdef([$1])])
|
---|
948 | # | m4_define([_arg1], [$1])
|
---|
949 | # | m4_define([_foreach],
|
---|
950 | # | [m4_if($2, [], ,
|
---|
951 | # | [m4_define([$1], [_arg1($2)])$3[]_foreach([$1], [m4_shift($2)], [$3])])])
|
---|
952 | #
|
---|
953 | #
|
---|
954 | # Now, just replace the `$2' with `m4_quote($2)' in the outer `m4_if'
|
---|
955 | # to improve robustness, and you come up with a nice implementation
|
---|
956 | # that doesn't require extra parentheses in the user's LIST.
|
---|
957 | #
|
---|
958 | # But wait - now the algorithm is quadratic, because every recursion of
|
---|
959 | # the algorithm keeps the entire LIST and merely adds another m4_shift to
|
---|
960 | # the quoted text. If the user has a lot of elements in LIST, you can
|
---|
961 | # bring the system to its knees with the memory m4 then requires, or trip
|
---|
962 | # the m4 --nesting-limit recursion factor. The only way to avoid
|
---|
963 | # quadratic growth is ensure m4_shift is expanded prior to the recursion.
|
---|
964 | # Hence the design below.
|
---|
965 | #
|
---|
966 | # The M4 manual now includes a chapter devoted to this issue, with
|
---|
967 | # the lessons learned from m4sugar. And still, this design is only
|
---|
968 | # optimal for M4 1.6; see foreach.m4 for yet more comments on why
|
---|
969 | # M4 1.4.x uses yet another implementation.
|
---|
970 |
|
---|
971 |
|
---|
972 | # m4_foreach(VARIABLE, LIST, EXPRESSION)
|
---|
973 | # --------------------------------------
|
---|
974 | #
|
---|
975 | # Expand EXPRESSION assigning each value of the LIST to VARIABLE.
|
---|
976 | # LIST should have the form `item_1, item_2, ..., item_n', i.e. the
|
---|
977 | # whole list must *quoted*. Quote members too if you don't want them
|
---|
978 | # to be expanded.
|
---|
979 | #
|
---|
980 | # This macro is robust to active symbols:
|
---|
981 | # | m4_define(active, [ACT, IVE])
|
---|
982 | # | m4_foreach(Var, [active, active], [-Var-])
|
---|
983 | # => -ACT--IVE--ACT--IVE-
|
---|
984 | #
|
---|
985 | # | m4_foreach(Var, [[active], [active]], [-Var-])
|
---|
986 | # => -ACT, IVE--ACT, IVE-
|
---|
987 | #
|
---|
988 | # | m4_foreach(Var, [[[active]], [[active]]], [-Var-])
|
---|
989 | # => -active--active-
|
---|
990 | #
|
---|
991 | # This macro is called frequently, so avoid extra expansions such as
|
---|
992 | # m4_ifval and dnl. Also, since $2 might be quite large, try to use it
|
---|
993 | # as little as possible in _m4_foreach; each extra use requires that much
|
---|
994 | # more memory for expansion. So, rather than directly compare $2 against
|
---|
995 | # [] and use m4_car/m4_cdr for recursion, we instead unbox the list (which
|
---|
996 | # requires swapping the argument order in the helper), insert an ignored
|
---|
997 | # third argument, and use m4_shift3 to detect when recursion is complete.
|
---|
998 | #
|
---|
999 | # Please keep foreach.m4 in sync with any adjustments made here.
|
---|
1000 | m4_define([m4_foreach],
|
---|
1001 | [m4_if([$2], [], [],
|
---|
1002 | [m4_pushdef([$1])_$0([$1], [$3], [], $2)m4_popdef([$1])])])
|
---|
1003 |
|
---|
1004 | m4_define([_m4_foreach],
|
---|
1005 | [m4_if([$#], [3], [],
|
---|
1006 | [m4_define([$1], [$4])$2[]$0([$1], [$2], m4_shift3($@))])])
|
---|
1007 |
|
---|
1008 |
|
---|
1009 | # m4_foreach_w(VARIABLE, LIST, EXPRESSION)
|
---|
1010 | # ----------------------------------------
|
---|
1011 | #
|
---|
1012 | # Like m4_foreach, but the list is whitespace separated.
|
---|
1013 | #
|
---|
1014 | # This macro is robust to active symbols:
|
---|
1015 | # m4_foreach_w([Var], [ active
|
---|
1016 | # b act\
|
---|
1017 | # ive ], [-Var-])end
|
---|
1018 | # => -active--b--active-end
|
---|
1019 | #
|
---|
1020 | m4_define([m4_foreach_w],
|
---|
1021 | [m4_foreach([$1], m4_split(m4_normalize([$2]), [ ]), [$3])])
|
---|
1022 |
|
---|
1023 |
|
---|
1024 | # m4_map(MACRO, LIST)
|
---|
1025 | # m4_mapall(MACRO, LIST)
|
---|
1026 | # ----------------------
|
---|
1027 | # Invoke MACRO($1), MACRO($2) etc. where $1, $2... are the elements of
|
---|
1028 | # LIST. $1, $2... must in turn be lists, appropriate for m4_apply.
|
---|
1029 | # If LIST contains an empty sublist, m4_map skips the expansion of
|
---|
1030 | # MACRO, while m4_mapall expands MACRO with no arguments.
|
---|
1031 | #
|
---|
1032 | # Since LIST may be quite large, we want to minimize how often it
|
---|
1033 | # appears in the expansion. Rather than use m4_car/m4_cdr iteration,
|
---|
1034 | # we unbox the list, ignore the second argument, and use m4_shift2 to
|
---|
1035 | # detect the end of recursion. The mismatch in () is intentional; see
|
---|
1036 | # _m4_map. For m4_map, an empty list behaves like an empty sublist
|
---|
1037 | # and gets ignored; for m4_mapall, we must special-case the empty
|
---|
1038 | # list.
|
---|
1039 | #
|
---|
1040 | # Please keep foreach.m4 in sync with any adjustments made here.
|
---|
1041 | m4_define([m4_map],
|
---|
1042 | [_m4_map([_m4_apply([$1]], [], $2)])
|
---|
1043 |
|
---|
1044 | m4_define([m4_mapall],
|
---|
1045 | [m4_if([$2], [], [],
|
---|
1046 | [_m4_map([m4_apply([$1]], [], $2)])])
|
---|
1047 |
|
---|
1048 |
|
---|
1049 | # m4_map_sep(MACRO, SEPARATOR, LIST)
|
---|
1050 | # m4_mapall_sep(MACRO, SEPARATOR, LIST)
|
---|
1051 | # -------------------------------------
|
---|
1052 | # Invoke MACRO($1), SEPARATOR, MACRO($2), ..., MACRO($N) where $1,
|
---|
1053 | # $2... $N are the elements of LIST, and are in turn lists appropriate
|
---|
1054 | # for m4_apply. SEPARATOR is expanded, in order to allow the creation
|
---|
1055 | # of a list of arguments by using a single-quoted comma as the
|
---|
1056 | # separator. For each empty sublist, m4_map_sep skips the expansion
|
---|
1057 | # of MACRO and SEPARATOR, while m4_mapall_sep expands MACRO with no
|
---|
1058 | # arguments.
|
---|
1059 | #
|
---|
1060 | # For m4_mapall_sep, merely expand the first iteration without the
|
---|
1061 | # separator, then include separator as part of subsequent recursion;
|
---|
1062 | # but avoid extra expansion of LIST's side-effects via a helper macro.
|
---|
1063 | # For m4_map_sep, things are trickier - we don't know if the first
|
---|
1064 | # list element is an empty sublist, so we must define a self-modifying
|
---|
1065 | # helper macro and use that as the separator instead.
|
---|
1066 | m4_define([m4_map_sep],
|
---|
1067 | [m4_pushdef([m4_Sep], [m4_define([m4_Sep], _m4_defn([m4_unquote]))])]dnl
|
---|
1068 | [_m4_map([_m4_apply([m4_Sep([$2])[]$1]], [], $3)m4_popdef([m4_Sep])])
|
---|
1069 |
|
---|
1070 | m4_define([m4_mapall_sep],
|
---|
1071 | [m4_if([$3], [], [], [_$0([$1], [$2], $3)])])
|
---|
1072 |
|
---|
1073 | m4_define([_m4_mapall_sep],
|
---|
1074 | [m4_apply([$1], [$3])_m4_map([m4_apply([$2[]$1]], m4_shift2($@))])
|
---|
1075 |
|
---|
1076 | # _m4_map(PREFIX, IGNORED, SUBLIST, ...)
|
---|
1077 | # --------------------------------------
|
---|
1078 | # Common implementation for all four m4_map variants. The mismatch in
|
---|
1079 | # the number of () is intentional. PREFIX must supply a form of
|
---|
1080 | # m4_apply, the open `(', and the MACRO to be applied. Each iteration
|
---|
1081 | # then appends `,', the current SUBLIST and the closing `)', then
|
---|
1082 | # recurses to the next SUBLIST. IGNORED is an aid to ending recursion
|
---|
1083 | # efficiently.
|
---|
1084 | #
|
---|
1085 | # Please keep foreach.m4 in sync with any adjustments made here.
|
---|
1086 | m4_define([_m4_map],
|
---|
1087 | [m4_if([$#], [2], [],
|
---|
1088 | [$1, [$3])$0([$1], m4_shift2($@))])])
|
---|
1089 |
|
---|
1090 | # m4_transform(EXPRESSION, ARG...)
|
---|
1091 | # --------------------------------
|
---|
1092 | # Expand EXPRESSION([ARG]) for each argument. More efficient than
|
---|
1093 | # m4_foreach([var], [ARG...], [EXPRESSION(m4_defn([var]))])
|
---|
1094 | #
|
---|
1095 | # Please keep foreach.m4 in sync with any adjustments made here.
|
---|
1096 | m4_define([m4_transform],
|
---|
1097 | [m4_if([$#], [0], [m4_fatal([$0: too few arguments: $#])],
|
---|
1098 | [$#], [1], [],
|
---|
1099 | [$#], [2], [$1([$2])[]],
|
---|
1100 | [$1([$2])[]$0([$1], m4_shift2($@))])])
|
---|
1101 |
|
---|
1102 |
|
---|
1103 | # m4_transform_pair(EXPRESSION, [END-EXPR = EXPRESSION], ARG...)
|
---|
1104 | # --------------------------------------------------------------
|
---|
1105 | # Perform a pairwise grouping of consecutive ARGs, by expanding
|
---|
1106 | # EXPRESSION([ARG1], [ARG2]). If there are an odd number of ARGs, the
|
---|
1107 | # final argument is expanded with END-EXPR([ARGn]).
|
---|
1108 | #
|
---|
1109 | # For example:
|
---|
1110 | # m4_define([show], [($*)m4_newline])dnl
|
---|
1111 | # m4_transform_pair([show], [], [a], [b], [c], [d], [e])dnl
|
---|
1112 | # => (a,b)
|
---|
1113 | # => (c,d)
|
---|
1114 | # => (e)
|
---|
1115 | #
|
---|
1116 | # Please keep foreach.m4 in sync with any adjustments made here.
|
---|
1117 | m4_define([m4_transform_pair],
|
---|
1118 | [m4_if([$#], [0], [m4_fatal([$0: too few arguments: $#])],
|
---|
1119 | [$#], [1], [m4_fatal([$0: too few arguments: $#: $1])],
|
---|
1120 | [$#], [2], [],
|
---|
1121 | [$#], [3], [m4_default([$2], [$1])([$3])[]],
|
---|
1122 | [$#], [4], [$1([$3], [$4])[]],
|
---|
1123 | [$1([$3], [$4])[]$0([$1], [$2], m4_shift(m4_shift3($@)))])])
|
---|
1124 |
|
---|
1125 |
|
---|
1126 | ## --------------------------- ##
|
---|
1127 | ## 9. More diversion support. ##
|
---|
1128 | ## --------------------------- ##
|
---|
1129 |
|
---|
1130 |
|
---|
1131 | # _m4_divert(DIVERSION-NAME or NUMBER)
|
---|
1132 | # ------------------------------------
|
---|
1133 | # If DIVERSION-NAME is the name of a diversion, return its number,
|
---|
1134 | # otherwise if it is a NUMBER return it.
|
---|
1135 | m4_define([_m4_divert],
|
---|
1136 | [m4_ifdef([_m4_divert($1)],
|
---|
1137 | [m4_indir([_m4_divert($1)])],
|
---|
1138 | [$1])])
|
---|
1139 |
|
---|
1140 | # KILL is only used to suppress output.
|
---|
1141 | m4_define([_m4_divert(KILL)], -1)
|
---|
1142 |
|
---|
1143 | # The empty diversion name is a synonym for 0.
|
---|
1144 | m4_define([_m4_divert()], 0)
|
---|
1145 |
|
---|
1146 |
|
---|
1147 | # _m4_divert_n_stack
|
---|
1148 | # ------------------
|
---|
1149 | # Print m4_divert_stack with newline prepended, if it's nonempty.
|
---|
1150 | m4_define([_m4_divert_n_stack],
|
---|
1151 | [m4_ifdef([m4_divert_stack], [
|
---|
1152 | _m4_defn([m4_divert_stack])])])
|
---|
1153 |
|
---|
1154 |
|
---|
1155 | # m4_divert(DIVERSION-NAME)
|
---|
1156 | # -------------------------
|
---|
1157 | # Change the diversion stream to DIVERSION-NAME.
|
---|
1158 | m4_define([m4_divert],
|
---|
1159 | [m4_define([m4_divert_stack], m4_location[: $0: $1]_m4_divert_n_stack)]dnl
|
---|
1160 | [m4_builtin([divert], _m4_divert([$1]))])
|
---|
1161 |
|
---|
1162 |
|
---|
1163 | # m4_divert_push(DIVERSION-NAME)
|
---|
1164 | # ------------------------------
|
---|
1165 | # Change the diversion stream to DIVERSION-NAME, while stacking old values.
|
---|
1166 | m4_define([m4_divert_push],
|
---|
1167 | [m4_pushdef([m4_divert_stack], m4_location[: $0: $1]_m4_divert_n_stack)]dnl
|
---|
1168 | [m4_pushdef([_m4_divert_diversion], [$1])]dnl
|
---|
1169 | [m4_builtin([divert], _m4_divert([$1]))])
|
---|
1170 |
|
---|
1171 |
|
---|
1172 | # m4_divert_pop([DIVERSION-NAME])
|
---|
1173 | # -------------------------------
|
---|
1174 | # Change the diversion stream to its previous value, unstacking it.
|
---|
1175 | # If specified, verify we left DIVERSION-NAME.
|
---|
1176 | # When we pop the last value from the stack, we divert to -1.
|
---|
1177 | m4_define([m4_divert_pop],
|
---|
1178 | [m4_ifndef([_m4_divert_diversion],
|
---|
1179 | [m4_fatal([too many m4_divert_pop])])]dnl
|
---|
1180 | [m4_if([$1], [], [],
|
---|
1181 | [$1], _m4_defn([_m4_divert_diversion]), [],
|
---|
1182 | [m4_fatal([$0($1): diversion mismatch: ]_m4_divert_n_stack)])]dnl
|
---|
1183 | [_m4_popdef([m4_divert_stack], [_m4_divert_diversion])]dnl
|
---|
1184 | [m4_builtin([divert],
|
---|
1185 | m4_ifdef([_m4_divert_diversion],
|
---|
1186 | [_m4_divert(_m4_defn([_m4_divert_diversion]))],
|
---|
1187 | -1))])
|
---|
1188 |
|
---|
1189 |
|
---|
1190 | # m4_divert_text(DIVERSION-NAME, CONTENT)
|
---|
1191 | # ---------------------------------------
|
---|
1192 | # Output CONTENT into DIVERSION-NAME (which may be a number actually).
|
---|
1193 | # An end of line is appended for free to CONTENT.
|
---|
1194 | m4_define([m4_divert_text],
|
---|
1195 | [m4_divert_push([$1])$2
|
---|
1196 | m4_divert_pop([$1])])
|
---|
1197 |
|
---|
1198 |
|
---|
1199 | # m4_divert_once(DIVERSION-NAME, CONTENT)
|
---|
1200 | # ---------------------------------------
|
---|
1201 | # Output CONTENT into DIVERSION-NAME once, if not already there.
|
---|
1202 | # An end of line is appended for free to CONTENT.
|
---|
1203 | m4_define([m4_divert_once],
|
---|
1204 | [m4_expand_once([m4_divert_text([$1], [$2])])])
|
---|
1205 |
|
---|
1206 |
|
---|
1207 | # m4_undivert(DIVERSION-NAME)
|
---|
1208 | # ---------------------------
|
---|
1209 | # Undivert DIVERSION-NAME. Unlike the M4 version, this only takes a single
|
---|
1210 | # diversion identifier, and should not be used to undivert files.
|
---|
1211 | m4_define([m4_undivert],
|
---|
1212 | [m4_builtin([undivert], _m4_divert([$1]))])
|
---|
1213 |
|
---|
1214 |
|
---|
1215 | ## --------------------------------------------- ##
|
---|
1216 | ## 10. Defining macros with bells and whistles. ##
|
---|
1217 | ## --------------------------------------------- ##
|
---|
1218 |
|
---|
1219 | # `m4_defun' is basically `m4_define' but it equips the macro with the
|
---|
1220 | # needed machinery for `m4_require'. A macro must be m4_defun'd if
|
---|
1221 | # either it is m4_require'd, or it m4_require's.
|
---|
1222 | #
|
---|
1223 | # Two things deserve attention and are detailed below:
|
---|
1224 | # 1. Implementation of m4_require
|
---|
1225 | # 2. Keeping track of the expansion stack
|
---|
1226 | #
|
---|
1227 | # 1. Implementation of m4_require
|
---|
1228 | # ===============================
|
---|
1229 | #
|
---|
1230 | # Of course m4_defun AC_PROVIDE's the macro, so that a macro which has
|
---|
1231 | # been expanded is not expanded again when m4_require'd, but the
|
---|
1232 | # difficult part is the proper expansion of macros when they are
|
---|
1233 | # m4_require'd.
|
---|
1234 | #
|
---|
1235 | # The implementation is based on two ideas, (i) using diversions to
|
---|
1236 | # prepare the expansion of the macro and its dependencies (by Franc,ois
|
---|
1237 | # Pinard), and (ii) expand the most recently m4_require'd macros _after_
|
---|
1238 | # the previous macros (by Axel Thimm).
|
---|
1239 | #
|
---|
1240 | #
|
---|
1241 | # The first idea: why use diversions?
|
---|
1242 | # -----------------------------------
|
---|
1243 | #
|
---|
1244 | # When a macro requires another, the other macro is expanded in new
|
---|
1245 | # diversion, GROW. When the outer macro is fully expanded, we first
|
---|
1246 | # undivert the most nested diversions (GROW - 1...), and finally
|
---|
1247 | # undivert GROW. To understand why we need several diversions,
|
---|
1248 | # consider the following example:
|
---|
1249 | #
|
---|
1250 | # | m4_defun([TEST1], [Test...REQUIRE([TEST2])1])
|
---|
1251 | # | m4_defun([TEST2], [Test...REQUIRE([TEST3])2])
|
---|
1252 | # | m4_defun([TEST3], [Test...3])
|
---|
1253 | #
|
---|
1254 | # Because m4_require is not required to be first in the outer macros, we
|
---|
1255 | # must keep the expansions of the various levels of m4_require separated.
|
---|
1256 | # Right before executing the epilogue of TEST1, we have:
|
---|
1257 | #
|
---|
1258 | # GROW - 2: Test...3
|
---|
1259 | # GROW - 1: Test...2
|
---|
1260 | # GROW: Test...1
|
---|
1261 | # BODY:
|
---|
1262 | #
|
---|
1263 | # Finally the epilogue of TEST1 undiverts GROW - 2, GROW - 1, and
|
---|
1264 | # GROW into the regular flow, BODY.
|
---|
1265 | #
|
---|
1266 | # GROW - 2:
|
---|
1267 | # GROW - 1:
|
---|
1268 | # GROW:
|
---|
1269 | # BODY: Test...3; Test...2; Test...1
|
---|
1270 | #
|
---|
1271 | # (The semicolons are here for clarification, but of course are not
|
---|
1272 | # emitted.) This is what Autoconf 2.0 (I think) to 2.13 (I'm sure)
|
---|
1273 | # implement.
|
---|
1274 | #
|
---|
1275 | #
|
---|
1276 | # The second idea: first required first out
|
---|
1277 | # -----------------------------------------
|
---|
1278 | #
|
---|
1279 | # The natural implementation of the idea above is buggy and produces
|
---|
1280 | # very surprising results in some situations. Let's consider the
|
---|
1281 | # following example to explain the bug:
|
---|
1282 | #
|
---|
1283 | # | m4_defun([TEST1], [REQUIRE([TEST2a])REQUIRE([TEST2b])])
|
---|
1284 | # | m4_defun([TEST2a], [])
|
---|
1285 | # | m4_defun([TEST2b], [REQUIRE([TEST3])])
|
---|
1286 | # | m4_defun([TEST3], [REQUIRE([TEST2a])])
|
---|
1287 | # |
|
---|
1288 | # | AC_INIT
|
---|
1289 | # | TEST1
|
---|
1290 | #
|
---|
1291 | # The dependencies between the macros are:
|
---|
1292 | #
|
---|
1293 | # 3 --- 2b
|
---|
1294 | # / \ is m4_require'd by
|
---|
1295 | # / \ left -------------------- right
|
---|
1296 | # 2a ------------ 1
|
---|
1297 | #
|
---|
1298 | # If you strictly apply the rules given in the previous section you get:
|
---|
1299 | #
|
---|
1300 | # GROW - 2: TEST3
|
---|
1301 | # GROW - 1: TEST2a; TEST2b
|
---|
1302 | # GROW: TEST1
|
---|
1303 | # BODY:
|
---|
1304 | #
|
---|
1305 | # (TEST2a, although required by TEST3 is not expanded in GROW - 3
|
---|
1306 | # because is has already been expanded before in GROW - 1, so it has
|
---|
1307 | # been AC_PROVIDE'd, so it is not expanded again) so when you undivert
|
---|
1308 | # the stack of diversions, you get:
|
---|
1309 | #
|
---|
1310 | # GROW - 2:
|
---|
1311 | # GROW - 1:
|
---|
1312 | # GROW:
|
---|
1313 | # BODY: TEST3; TEST2a; TEST2b; TEST1
|
---|
1314 | #
|
---|
1315 | # i.e., TEST2a is expanded after TEST3 although the latter required the
|
---|
1316 | # former.
|
---|
1317 | #
|
---|
1318 | # Starting from 2.50, we use an implementation provided by Axel Thimm.
|
---|
1319 | # The idea is simple: the order in which macros are emitted must be the
|
---|
1320 | # same as the one in which macros are expanded. (The bug above can
|
---|
1321 | # indeed be described as: a macro has been AC_PROVIDE'd before its
|
---|
1322 | # dependent, but it is emitted after: the lack of correlation between
|
---|
1323 | # emission and expansion order is guilty).
|
---|
1324 | #
|
---|
1325 | # How to do that? You keep the stack of diversions to elaborate the
|
---|
1326 | # macros, but each time a macro is fully expanded, emit it immediately.
|
---|
1327 | #
|
---|
1328 | # In the example above, when TEST2a is expanded, but it's epilogue is
|
---|
1329 | # not run yet, you have:
|
---|
1330 | #
|
---|
1331 | # GROW - 2:
|
---|
1332 | # GROW - 1: TEST2a
|
---|
1333 | # GROW: Elaboration of TEST1
|
---|
1334 | # BODY:
|
---|
1335 | #
|
---|
1336 | # The epilogue of TEST2a emits it immediately:
|
---|
1337 | #
|
---|
1338 | # GROW - 2:
|
---|
1339 | # GROW - 1:
|
---|
1340 | # GROW: Elaboration of TEST1
|
---|
1341 | # BODY: TEST2a
|
---|
1342 | #
|
---|
1343 | # TEST2b then requires TEST3, so right before the epilogue of TEST3, you
|
---|
1344 | # have:
|
---|
1345 | #
|
---|
1346 | # GROW - 2: TEST3
|
---|
1347 | # GROW - 1: Elaboration of TEST2b
|
---|
1348 | # GROW: Elaboration of TEST1
|
---|
1349 | # BODY: TEST2a
|
---|
1350 | #
|
---|
1351 | # The epilogue of TEST3 emits it:
|
---|
1352 | #
|
---|
1353 | # GROW - 2:
|
---|
1354 | # GROW - 1: Elaboration of TEST2b
|
---|
1355 | # GROW: Elaboration of TEST1
|
---|
1356 | # BODY: TEST2a; TEST3
|
---|
1357 | #
|
---|
1358 | # TEST2b is now completely expanded, and emitted:
|
---|
1359 | #
|
---|
1360 | # GROW - 2:
|
---|
1361 | # GROW - 1:
|
---|
1362 | # GROW: Elaboration of TEST1
|
---|
1363 | # BODY: TEST2a; TEST3; TEST2b
|
---|
1364 | #
|
---|
1365 | # and finally, TEST1 is finished and emitted:
|
---|
1366 | #
|
---|
1367 | # GROW - 2:
|
---|
1368 | # GROW - 1:
|
---|
1369 | # GROW:
|
---|
1370 | # BODY: TEST2a; TEST3; TEST2b: TEST1
|
---|
1371 | #
|
---|
1372 | # The idea is simple, but the implementation is a bit evolved. If you
|
---|
1373 | # are like me, you will want to see the actual functioning of this
|
---|
1374 | # implementation to be convinced. The next section gives the full
|
---|
1375 | # details.
|
---|
1376 | #
|
---|
1377 | #
|
---|
1378 | # The Axel Thimm implementation at work
|
---|
1379 | # -------------------------------------
|
---|
1380 | #
|
---|
1381 | # We consider the macros above, and this configure.ac:
|
---|
1382 | #
|
---|
1383 | # AC_INIT
|
---|
1384 | # TEST1
|
---|
1385 | #
|
---|
1386 | # You should keep the definitions of _m4_defun_pro, _m4_defun_epi, and
|
---|
1387 | # m4_require at hand to follow the steps.
|
---|
1388 | #
|
---|
1389 | # This implements tries not to assume that the current diversion is
|
---|
1390 | # BODY, so as soon as a macro (m4_defun'd) is expanded, we first
|
---|
1391 | # record the current diversion under the name _m4_divert_dump (denoted
|
---|
1392 | # DUMP below for short). This introduces an important difference with
|
---|
1393 | # the previous versions of Autoconf: you cannot use m4_require if you
|
---|
1394 | # are not inside an m4_defun'd macro, and especially, you cannot
|
---|
1395 | # m4_require directly from the top level.
|
---|
1396 | #
|
---|
1397 | # We have not tried to simulate the old behavior (better yet, we
|
---|
1398 | # diagnose it), because it is too dangerous: a macro m4_require'd from
|
---|
1399 | # the top level is expanded before the body of `configure', i.e., before
|
---|
1400 | # any other test was run. I let you imagine the result of requiring
|
---|
1401 | # AC_STDC_HEADERS for instance, before AC_PROG_CC was actually run....
|
---|
1402 | #
|
---|
1403 | # After AC_INIT was run, the current diversion is BODY.
|
---|
1404 | # * AC_INIT was run
|
---|
1405 | # DUMP: undefined
|
---|
1406 | # diversion stack: BODY |-
|
---|
1407 | #
|
---|
1408 | # * TEST1 is expanded
|
---|
1409 | # The prologue of TEST1 sets _m4_divert_dump, which is the diversion
|
---|
1410 | # where the current elaboration will be dumped, to the current
|
---|
1411 | # diversion. It also m4_divert_push to GROW, where the full
|
---|
1412 | # expansion of TEST1 and its dependencies will be elaborated.
|
---|
1413 | # DUMP: BODY
|
---|
1414 | # BODY: empty
|
---|
1415 | # diversions: GROW, BODY |-
|
---|
1416 | #
|
---|
1417 | # * TEST1 requires TEST2a
|
---|
1418 | # _m4_require_call m4_divert_pushes another temporary diversion,
|
---|
1419 | # GROW - 1, and expands TEST2a in there.
|
---|
1420 | # DUMP: BODY
|
---|
1421 | # BODY: empty
|
---|
1422 | # GROW - 1: TEST2a
|
---|
1423 | # diversions: GROW - 1, GROW, BODY |-
|
---|
1424 | # Than the content of the temporary diversion is moved to DUMP and the
|
---|
1425 | # temporary diversion is popped.
|
---|
1426 | # DUMP: BODY
|
---|
1427 | # BODY: TEST2a
|
---|
1428 | # diversions: GROW, BODY |-
|
---|
1429 | #
|
---|
1430 | # * TEST1 requires TEST2b
|
---|
1431 | # Again, _m4_require_call pushes GROW - 1 and heads to expand TEST2b.
|
---|
1432 | # DUMP: BODY
|
---|
1433 | # BODY: TEST2a
|
---|
1434 | # diversions: GROW - 1, GROW, BODY |-
|
---|
1435 | #
|
---|
1436 | # * TEST2b requires TEST3
|
---|
1437 | # _m4_require_call pushes GROW - 2 and expands TEST3 here.
|
---|
1438 | # (TEST3 requires TEST2a, but TEST2a has already been m4_provide'd, so
|
---|
1439 | # nothing happens.)
|
---|
1440 | # DUMP: BODY
|
---|
1441 | # BODY: TEST2a
|
---|
1442 | # GROW - 2: TEST3
|
---|
1443 | # diversions: GROW - 2, GROW - 1, GROW, BODY |-
|
---|
1444 | # Than the diversion is appended to DUMP, and popped.
|
---|
1445 | # DUMP: BODY
|
---|
1446 | # BODY: TEST2a; TEST3
|
---|
1447 | # diversions: GROW - 1, GROW, BODY |-
|
---|
1448 | #
|
---|
1449 | # * TEST1 requires TEST2b (contd.)
|
---|
1450 | # The content of TEST2b is expanded...
|
---|
1451 | # DUMP: BODY
|
---|
1452 | # BODY: TEST2a; TEST3
|
---|
1453 | # GROW - 1: TEST2b,
|
---|
1454 | # diversions: GROW - 1, GROW, BODY |-
|
---|
1455 | # ... and moved to DUMP.
|
---|
1456 | # DUMP: BODY
|
---|
1457 | # BODY: TEST2a; TEST3; TEST2b
|
---|
1458 | # diversions: GROW, BODY |-
|
---|
1459 | #
|
---|
1460 | # * TEST1 is expanded: epilogue
|
---|
1461 | # TEST1's own content is in GROW...
|
---|
1462 | # DUMP: BODY
|
---|
1463 | # BODY: TEST2a; TEST3; TEST2b
|
---|
1464 | # GROW: TEST1
|
---|
1465 | # diversions: BODY |-
|
---|
1466 | # ... and it's epilogue moves it to DUMP and then undefines DUMP.
|
---|
1467 | # DUMP: undefined
|
---|
1468 | # BODY: TEST2a; TEST3; TEST2b; TEST1
|
---|
1469 | # diversions: BODY |-
|
---|
1470 | #
|
---|
1471 | #
|
---|
1472 | # 2. Keeping track of the expansion stack
|
---|
1473 | # =======================================
|
---|
1474 | #
|
---|
1475 | # When M4 expansion goes wrong it is often extremely hard to find the
|
---|
1476 | # path amongst macros that drove to the failure. What is needed is
|
---|
1477 | # the stack of macro `calls'. One could imagine that GNU M4 would
|
---|
1478 | # maintain a stack of macro expansions, unfortunately it doesn't, so
|
---|
1479 | # we do it by hand. This is of course extremely costly, but the help
|
---|
1480 | # this stack provides is worth it. Nevertheless to limit the
|
---|
1481 | # performance penalty this is implemented only for m4_defun'd macros,
|
---|
1482 | # not for define'd macros.
|
---|
1483 | #
|
---|
1484 | # The scheme is simplistic: each time we enter an m4_defun'd macros,
|
---|
1485 | # we prepend its name in m4_expansion_stack, and when we exit the
|
---|
1486 | # macro, we remove it (thanks to pushdef/popdef).
|
---|
1487 | #
|
---|
1488 | # In addition, we want to detect circular m4_require dependencies.
|
---|
1489 | # Each time we expand a macro FOO we define _m4_expanding(FOO); and
|
---|
1490 | # m4_require(BAR) simply checks whether _m4_expanding(BAR) is defined.
|
---|
1491 |
|
---|
1492 |
|
---|
1493 | # m4_expansion_stack_push(TEXT)
|
---|
1494 | # -----------------------------
|
---|
1495 | m4_define([m4_expansion_stack_push],
|
---|
1496 | [m4_pushdef([m4_expansion_stack],
|
---|
1497 | [$1]m4_ifdef([m4_expansion_stack], [
|
---|
1498 | _m4_defn([m4_expansion_stack])]))])
|
---|
1499 |
|
---|
1500 |
|
---|
1501 | # m4_expansion_stack_pop
|
---|
1502 | # ----------------------
|
---|
1503 | m4_define([m4_expansion_stack_pop],
|
---|
1504 | [m4_popdef([m4_expansion_stack])])
|
---|
1505 |
|
---|
1506 |
|
---|
1507 | # m4_expansion_stack_dump
|
---|
1508 | # -----------------------
|
---|
1509 | # Dump the expansion stack.
|
---|
1510 | m4_define([m4_expansion_stack_dump],
|
---|
1511 | [m4_ifdef([m4_expansion_stack],
|
---|
1512 | [m4_errprintn(_m4_defn([m4_expansion_stack]))])dnl
|
---|
1513 | m4_errprintn(m4_location[: the top level])])
|
---|
1514 |
|
---|
1515 |
|
---|
1516 | # _m4_divert(GROW)
|
---|
1517 | # ----------------
|
---|
1518 | # This diversion is used by the m4_defun/m4_require machinery. It is
|
---|
1519 | # important to keep room before GROW because for each nested
|
---|
1520 | # AC_REQUIRE we use an additional diversion (i.e., two m4_require's
|
---|
1521 | # will use GROW - 2. More than 3 levels has never seemed to be
|
---|
1522 | # needed.)
|
---|
1523 | #
|
---|
1524 | # ...
|
---|
1525 | # - GROW - 2
|
---|
1526 | # m4_require'd code, 2 level deep
|
---|
1527 | # - GROW - 1
|
---|
1528 | # m4_require'd code, 1 level deep
|
---|
1529 | # - GROW
|
---|
1530 | # m4_defun'd macros are elaborated here.
|
---|
1531 |
|
---|
1532 | m4_define([_m4_divert(GROW)], 10000)
|
---|
1533 |
|
---|
1534 |
|
---|
1535 | # _m4_defun_pro(MACRO-NAME)
|
---|
1536 | # -------------------------
|
---|
1537 | # The prologue for Autoconf macros.
|
---|
1538 | #
|
---|
1539 | # This is called frequently, so minimize the number of macro invocations
|
---|
1540 | # by avoiding dnl and m4_defn overhead.
|
---|
1541 | m4_define([_m4_defun_pro],
|
---|
1542 | m4_do([[m4_ifdef([m4_expansion_stack], [], [_m4_defun_pro_outer[]])]],
|
---|
1543 | [[m4_expansion_stack_push(_m4_defn(
|
---|
1544 | [m4_location($1)])[: $1 is expanded from...])]],
|
---|
1545 | [[m4_pushdef([_m4_expanding($1)])]]))
|
---|
1546 |
|
---|
1547 | m4_define([_m4_defun_pro_outer],
|
---|
1548 | [m4_copy([_m4_divert_diversion], [_m4_divert_dump])m4_divert_push([GROW])])
|
---|
1549 |
|
---|
1550 | # _m4_defun_epi(MACRO-NAME)
|
---|
1551 | # -------------------------
|
---|
1552 | # The Epilogue for Autoconf macros. MACRO-NAME only helps tracing
|
---|
1553 | # the PRO/EPI pairs.
|
---|
1554 | #
|
---|
1555 | # This is called frequently, so minimize the number of macro invocations
|
---|
1556 | # by avoiding dnl and m4_popdef overhead.
|
---|
1557 | m4_define([_m4_defun_epi],
|
---|
1558 | m4_do([[_m4_popdef([_m4_expanding($1)])]],
|
---|
1559 | [[m4_expansion_stack_pop()]],
|
---|
1560 | [[m4_ifdef([m4_expansion_stack], [], [_m4_defun_epi_outer[]])]],
|
---|
1561 | [[m4_provide([$1])]]))
|
---|
1562 |
|
---|
1563 | m4_define([_m4_defun_epi_outer],
|
---|
1564 | [_m4_undefine([_m4_divert_dump])m4_divert_pop([GROW])m4_undivert([GROW])])
|
---|
1565 |
|
---|
1566 |
|
---|
1567 | # m4_defun(NAME, EXPANSION)
|
---|
1568 | # -------------------------
|
---|
1569 | # Define a macro which automatically provides itself. Add machinery
|
---|
1570 | # so the macro automatically switches expansion to the diversion
|
---|
1571 | # stack if it is not already using it. In this case, once finished,
|
---|
1572 | # it will bring back all the code accumulated in the diversion stack.
|
---|
1573 | # This, combined with m4_require, achieves the topological ordering of
|
---|
1574 | # macros. We don't use this macro to define some frequently called
|
---|
1575 | # macros that are not involved in ordering constraints, to save m4
|
---|
1576 | # processing.
|
---|
1577 | m4_define([m4_defun],
|
---|
1578 | [m4_define([m4_location($1)], m4_location)dnl
|
---|
1579 | m4_define([$1],
|
---|
1580 | [_m4_defun_pro([$1])$2[]_m4_defun_epi([$1])])])
|
---|
1581 |
|
---|
1582 |
|
---|
1583 | # m4_defun_once(NAME, EXPANSION)
|
---|
1584 | # ------------------------------
|
---|
1585 | # As m4_defun, but issues the EXPANSION only once, and warns if used
|
---|
1586 | # several times.
|
---|
1587 | m4_define([m4_defun_once],
|
---|
1588 | [m4_define([m4_location($1)], m4_location)dnl
|
---|
1589 | m4_define([$1],
|
---|
1590 | [m4_provide_if([$1],
|
---|
1591 | [m4_warn([syntax], [$1 invoked multiple times])],
|
---|
1592 | [_m4_defun_pro([$1])$2[]_m4_defun_epi([$1])])])])
|
---|
1593 |
|
---|
1594 |
|
---|
1595 | # m4_pattern_forbid(ERE, [WHY])
|
---|
1596 | # -----------------------------
|
---|
1597 | # Declare that no token matching the forbidden extended regular
|
---|
1598 | # expression ERE should be seen in the output unless...
|
---|
1599 | m4_define([m4_pattern_forbid], [])
|
---|
1600 |
|
---|
1601 |
|
---|
1602 | # m4_pattern_allow(ERE)
|
---|
1603 | # ---------------------
|
---|
1604 | # ... that token also matches the allowed extended regular expression ERE.
|
---|
1605 | # Both used via traces.
|
---|
1606 | m4_define([m4_pattern_allow], [])
|
---|
1607 |
|
---|
1608 |
|
---|
1609 | ## --------------------------------- ##
|
---|
1610 | ## 11. Dependencies between macros. ##
|
---|
1611 | ## --------------------------------- ##
|
---|
1612 |
|
---|
1613 |
|
---|
1614 | # m4_before(THIS-MACRO-NAME, CALLED-MACRO-NAME)
|
---|
1615 | # ---------------------------------------------
|
---|
1616 | # Issue a warning if CALLED-MACRO-NAME was called before THIS-MACRO-NAME.
|
---|
1617 | m4_define([m4_before],
|
---|
1618 | [m4_provide_if([$2],
|
---|
1619 | [m4_warn([syntax], [$2 was called before $1])])])
|
---|
1620 |
|
---|
1621 |
|
---|
1622 | # m4_require(NAME-TO-CHECK, [BODY-TO-EXPAND = NAME-TO-CHECK])
|
---|
1623 | # -----------------------------------------------------------
|
---|
1624 | # If NAME-TO-CHECK has never been expanded (actually, if it is not
|
---|
1625 | # m4_provide'd), expand BODY-TO-EXPAND *before* the current macro
|
---|
1626 | # expansion. Once expanded, emit it in _m4_divert_dump. Keep track
|
---|
1627 | # of the m4_require chain in m4_expansion_stack.
|
---|
1628 | #
|
---|
1629 | # The normal cases are:
|
---|
1630 | #
|
---|
1631 | # - NAME-TO-CHECK == BODY-TO-EXPAND
|
---|
1632 | # Which you can use for regular macros with or without arguments, e.g.,
|
---|
1633 | # m4_require([AC_PROG_CC], [AC_PROG_CC])
|
---|
1634 | # m4_require([AC_CHECK_HEADERS(limits.h)], [AC_CHECK_HEADERS(limits.h)])
|
---|
1635 | # which is just the same as
|
---|
1636 | # m4_require([AC_PROG_CC])
|
---|
1637 | # m4_require([AC_CHECK_HEADERS(limits.h)])
|
---|
1638 | #
|
---|
1639 | # - BODY-TO-EXPAND == m4_indir([NAME-TO-CHECK])
|
---|
1640 | # In the case of macros with irregular names. For instance:
|
---|
1641 | # m4_require([AC_LANG_COMPILER(C)], [indir([AC_LANG_COMPILER(C)])])
|
---|
1642 | # which means `if the macro named `AC_LANG_COMPILER(C)' (the parens are
|
---|
1643 | # part of the name, it is not an argument) has not been run, then
|
---|
1644 | # call it.'
|
---|
1645 | # Had you used
|
---|
1646 | # m4_require([AC_LANG_COMPILER(C)], [AC_LANG_COMPILER(C)])
|
---|
1647 | # then m4_require would have tried to expand `AC_LANG_COMPILER(C)', i.e.,
|
---|
1648 | # call the macro `AC_LANG_COMPILER' with `C' as argument.
|
---|
1649 | #
|
---|
1650 | # You could argue that `AC_LANG_COMPILER', when it receives an argument
|
---|
1651 | # such as `C' should dispatch the call to `AC_LANG_COMPILER(C)'. But this
|
---|
1652 | # `extension' prevents `AC_LANG_COMPILER' from having actual arguments that
|
---|
1653 | # it passes to `AC_LANG_COMPILER(C)'.
|
---|
1654 | #
|
---|
1655 | # This is called frequently, so minimize the number of macro invocations
|
---|
1656 | # by avoiding dnl and other overhead on the common path.
|
---|
1657 | m4_define([m4_require],
|
---|
1658 | m4_do([[m4_ifdef([_m4_expanding($1)],
|
---|
1659 | [m4_fatal([$0: circular dependency of $1])])]],
|
---|
1660 | [[m4_ifdef([_m4_divert_dump], [],
|
---|
1661 | [m4_fatal([$0($1): cannot be used outside of an ]dnl
|
---|
1662 | m4_bmatch([$0], [^AC_], [[AC_DEFUN]], [[m4_defun]])['d macro])])]],
|
---|
1663 | [[m4_provide_if([$1],
|
---|
1664 | [],
|
---|
1665 | [_m4_require_call([$1], [$2])])]]))
|
---|
1666 |
|
---|
1667 |
|
---|
1668 | # _m4_require_call(NAME-TO-CHECK, [BODY-TO-EXPAND = NAME-TO-CHECK])
|
---|
1669 | # -----------------------------------------------------------------
|
---|
1670 | # If m4_require decides to expand the body, it calls this macro.
|
---|
1671 | #
|
---|
1672 | # This is called frequently, so minimize the number of macro invocations
|
---|
1673 | # by avoiding dnl and other overhead on the common path.
|
---|
1674 | m4_define([_m4_require_call],
|
---|
1675 | m4_do([[m4_define([_m4_divert_grow], m4_decr(_m4_divert_grow))]],
|
---|
1676 | [[m4_divert_push(_m4_divert_grow)]],
|
---|
1677 | [[m4_default([$2], [$1])
|
---|
1678 | m4_provide_if([$1],
|
---|
1679 | [],
|
---|
1680 | [m4_warn([syntax],
|
---|
1681 | [$1 is m4_require'd but not m4_defun'd])])]],
|
---|
1682 | [[m4_divert(_m4_defn([_m4_divert_dump]))]],
|
---|
1683 | [[m4_undivert(_m4_divert_grow)]],
|
---|
1684 | [[m4_divert_pop(_m4_divert_grow)]],
|
---|
1685 | [[m4_define([_m4_divert_grow], m4_incr(_m4_divert_grow))]]))
|
---|
1686 |
|
---|
1687 |
|
---|
1688 | # _m4_divert_grow
|
---|
1689 | # ---------------
|
---|
1690 | # The counter for _m4_require_call.
|
---|
1691 | m4_define([_m4_divert_grow], _m4_divert([GROW]))
|
---|
1692 |
|
---|
1693 |
|
---|
1694 | # m4_expand_once(TEXT, [WITNESS = TEXT])
|
---|
1695 | # --------------------------------------
|
---|
1696 | # If TEXT has never been expanded, expand it *here*. Use WITNESS as
|
---|
1697 | # as a memory that TEXT has already been expanded.
|
---|
1698 | m4_define([m4_expand_once],
|
---|
1699 | [m4_provide_if(m4_ifval([$2], [[$2]], [[$1]]),
|
---|
1700 | [],
|
---|
1701 | [m4_provide(m4_ifval([$2], [[$2]], [[$1]]))[]$1])])
|
---|
1702 |
|
---|
1703 |
|
---|
1704 | # m4_provide(MACRO-NAME)
|
---|
1705 | # ----------------------
|
---|
1706 | m4_define([m4_provide],
|
---|
1707 | [m4_define([m4_provide($1)])])
|
---|
1708 |
|
---|
1709 |
|
---|
1710 | # m4_provide_if(MACRO-NAME, IF-PROVIDED, IF-NOT-PROVIDED)
|
---|
1711 | # -------------------------------------------------------
|
---|
1712 | # If MACRO-NAME is provided do IF-PROVIDED, else IF-NOT-PROVIDED.
|
---|
1713 | # The purpose of this macro is to provide the user with a means to
|
---|
1714 | # check macros which are provided without letting her know how the
|
---|
1715 | # information is coded.
|
---|
1716 | m4_define([m4_provide_if],
|
---|
1717 | [m4_ifdef([m4_provide($1)],
|
---|
1718 | [$2], [$3])])
|
---|
1719 |
|
---|
1720 |
|
---|
1721 | ## --------------------- ##
|
---|
1722 | ## 12. Text processing. ##
|
---|
1723 | ## --------------------- ##
|
---|
1724 |
|
---|
1725 |
|
---|
1726 | # m4_cr_letters
|
---|
1727 | # m4_cr_LETTERS
|
---|
1728 | # m4_cr_Letters
|
---|
1729 | # -------------
|
---|
1730 | m4_define([m4_cr_letters], [abcdefghijklmnopqrstuvwxyz])
|
---|
1731 | m4_define([m4_cr_LETTERS], [ABCDEFGHIJKLMNOPQRSTUVWXYZ])
|
---|
1732 | m4_define([m4_cr_Letters],
|
---|
1733 | m4_defn([m4_cr_letters])dnl
|
---|
1734 | m4_defn([m4_cr_LETTERS])dnl
|
---|
1735 | )
|
---|
1736 |
|
---|
1737 |
|
---|
1738 | # m4_cr_digits
|
---|
1739 | # ------------
|
---|
1740 | m4_define([m4_cr_digits], [0123456789])
|
---|
1741 |
|
---|
1742 |
|
---|
1743 | # m4_cr_alnum
|
---|
1744 | # -----------
|
---|
1745 | m4_define([m4_cr_alnum],
|
---|
1746 | m4_defn([m4_cr_Letters])dnl
|
---|
1747 | m4_defn([m4_cr_digits])dnl
|
---|
1748 | )
|
---|
1749 |
|
---|
1750 |
|
---|
1751 | # m4_cr_symbols1
|
---|
1752 | # m4_cr_symbols2
|
---|
1753 | # -------------------------------
|
---|
1754 | m4_define([m4_cr_symbols1],
|
---|
1755 | m4_defn([m4_cr_Letters])dnl
|
---|
1756 | _)
|
---|
1757 |
|
---|
1758 | m4_define([m4_cr_symbols2],
|
---|
1759 | m4_defn([m4_cr_symbols1])dnl
|
---|
1760 | m4_defn([m4_cr_digits])dnl
|
---|
1761 | )
|
---|
1762 |
|
---|
1763 | # m4_cr_all
|
---|
1764 | # ---------
|
---|
1765 | # The character range representing everything, with `-' as the last
|
---|
1766 | # character, since it is special to m4_translit. Use with care, because
|
---|
1767 | # it contains characters special to M4 (fortunately, both ASCII and EBCDIC
|
---|
1768 | # have [] in order, so m4_defn([m4_cr_all]) remains a valid string). It
|
---|
1769 | # also contains characters special to terminals, so it should never be
|
---|
1770 | # displayed in an error message. Also, attempts to map [ and ] to other
|
---|
1771 | # characters via m4_translit must deal with the fact that m4_translit does
|
---|
1772 | # not add quotes to the output.
|
---|
1773 | #
|
---|
1774 | # It is mainly useful in generating inverted character range maps, for use
|
---|
1775 | # in places where m4_translit is faster than an equivalent m4_bpatsubst;
|
---|
1776 | # the regex `[^a-z]' is equivalent to:
|
---|
1777 | # m4_translit(m4_dquote(m4_defn([m4_cr_all])), [a-z])
|
---|
1778 | m4_define([m4_cr_all],
|
---|
1779 | m4_translit(m4_dquote(m4_format(m4_dquote(m4_for(
|
---|
1780 | ,1,255,,[[%c]]))m4_for([i],1,255,,[,i]))), [-])-)
|
---|
1781 |
|
---|
1782 |
|
---|
1783 | # _m4_define_cr_not(CATEGORY)
|
---|
1784 | # ---------------------------
|
---|
1785 | # Define m4_cr_not_CATEGORY as the inverse of m4_cr_CATEGORY.
|
---|
1786 | m4_define([_m4_define_cr_not],
|
---|
1787 | [m4_define([m4_cr_not_$1],
|
---|
1788 | m4_translit(m4_dquote(m4_defn([m4_cr_all])),
|
---|
1789 | m4_defn([m4_cr_$1])))])
|
---|
1790 |
|
---|
1791 |
|
---|
1792 | # m4_cr_not_letters
|
---|
1793 | # m4_cr_not_LETTERS
|
---|
1794 | # m4_cr_not_Letters
|
---|
1795 | # m4_cr_not_digits
|
---|
1796 | # m4_cr_not_alnum
|
---|
1797 | # m4_cr_not_symbols1
|
---|
1798 | # m4_cr_not_symbols2
|
---|
1799 | # ------------------
|
---|
1800 | # Inverse character sets
|
---|
1801 | _m4_define_cr_not([letters])
|
---|
1802 | _m4_define_cr_not([LETTERS])
|
---|
1803 | _m4_define_cr_not([Letters])
|
---|
1804 | _m4_define_cr_not([digits])
|
---|
1805 | _m4_define_cr_not([alnum])
|
---|
1806 | _m4_define_cr_not([symbols1])
|
---|
1807 | _m4_define_cr_not([symbols2])
|
---|
1808 |
|
---|
1809 |
|
---|
1810 | # m4_newline
|
---|
1811 | # ----------
|
---|
1812 | # Expands to a newline. Exists for formatting reasons.
|
---|
1813 | m4_define([m4_newline], [
|
---|
1814 | ])
|
---|
1815 |
|
---|
1816 |
|
---|
1817 | # m4_re_escape(STRING)
|
---|
1818 | # --------------------
|
---|
1819 | # Escape RE active characters in STRING.
|
---|
1820 | m4_define([m4_re_escape],
|
---|
1821 | [m4_bpatsubst([$1],
|
---|
1822 | [[][*+.?\^$]], [\\\&])])
|
---|
1823 |
|
---|
1824 |
|
---|
1825 | # m4_re_string
|
---|
1826 | # ------------
|
---|
1827 | # Regexp for `[a-zA-Z_0-9]*'
|
---|
1828 | # m4_dquote provides literal [] for the character class.
|
---|
1829 | m4_define([m4_re_string],
|
---|
1830 | m4_dquote(m4_defn([m4_cr_symbols2]))dnl
|
---|
1831 | [*]dnl
|
---|
1832 | )
|
---|
1833 |
|
---|
1834 |
|
---|
1835 | # m4_re_word
|
---|
1836 | # ----------
|
---|
1837 | # Regexp for `[a-zA-Z_][a-zA-Z_0-9]*'
|
---|
1838 | m4_define([m4_re_word],
|
---|
1839 | m4_dquote(m4_defn([m4_cr_symbols1]))dnl
|
---|
1840 | m4_defn([m4_re_string])dnl
|
---|
1841 | )
|
---|
1842 |
|
---|
1843 |
|
---|
1844 | # m4_tolower(STRING)
|
---|
1845 | # m4_toupper(STRING)
|
---|
1846 | # ------------------
|
---|
1847 | # These macros convert STRING to lowercase or uppercase.
|
---|
1848 | #
|
---|
1849 | # Rather than expand the m4_defn each time, we inline them up front.
|
---|
1850 | m4_define([m4_tolower],
|
---|
1851 | [m4_translit([$1], ]m4_dquote(m4_defn([m4_cr_LETTERS]))[,
|
---|
1852 | ]m4_dquote(m4_defn([m4_cr_letters]))[)])
|
---|
1853 | m4_define([m4_toupper],
|
---|
1854 | [m4_translit([$1], ]m4_dquote(m4_defn([m4_cr_letters]))[,
|
---|
1855 | ]m4_dquote(m4_defn([m4_cr_LETTERS]))[)])
|
---|
1856 |
|
---|
1857 |
|
---|
1858 | # m4_split(STRING, [REGEXP])
|
---|
1859 | # --------------------------
|
---|
1860 | #
|
---|
1861 | # Split STRING into an m4 list of quoted elements. The elements are
|
---|
1862 | # quoted with [ and ]. Beginning spaces and end spaces *are kept*.
|
---|
1863 | # Use m4_strip to remove them.
|
---|
1864 | #
|
---|
1865 | # REGEXP specifies where to split. Default is [\t ]+.
|
---|
1866 | #
|
---|
1867 | # If STRING is empty, the result is an empty list.
|
---|
1868 | #
|
---|
1869 | # Pay attention to the m4_changequotes. When m4 reads the definition of
|
---|
1870 | # m4_split, it still has quotes set to [ and ]. Luckily, these are matched
|
---|
1871 | # in the macro body, so the definition is stored correctly. Use the same
|
---|
1872 | # alternate quotes as m4_noquote; it must be unlikely to appear in $1.
|
---|
1873 | #
|
---|
1874 | # Also, notice that $1 is quoted twice, since we want the result to
|
---|
1875 | # be quoted. Then you should understand that the argument of
|
---|
1876 | # patsubst is -=<{(STRING)}>=- (i.e., with additional -=<{( and )}>=-).
|
---|
1877 | #
|
---|
1878 | # This macro is safe on active symbols, i.e.:
|
---|
1879 | # m4_define(active, ACTIVE)
|
---|
1880 | # m4_split([active active ])end
|
---|
1881 | # => [active], [active], []end
|
---|
1882 | #
|
---|
1883 | # Optimize on regex of ` ' (space), since m4_foreach_w already guarantees
|
---|
1884 | # that the list contains single space separators, and a common case is
|
---|
1885 | # splitting a single-element list. This macro is called frequently,
|
---|
1886 | # so avoid unnecessary dnl inside the definition.
|
---|
1887 | m4_define([m4_split],
|
---|
1888 | [m4_if([$1], [], [],
|
---|
1889 | [$2], [ ], [m4_if(m4_index([$1], [ ]), [-1], [[[$1]]], [_$0($@)])],
|
---|
1890 | [$2], [], [_$0([$1], [[ ]+])],
|
---|
1891 | [_$0($@)])])
|
---|
1892 |
|
---|
1893 | m4_define([_m4_split],
|
---|
1894 | [m4_changequote([-=<{(],[)}>=-])]dnl
|
---|
1895 | [[m4_bpatsubst(-=<{(-=<{($1)}>=-)}>=-, -=<{($2)}>=-,
|
---|
1896 | -=<{(], [)}>=-)]m4_changequote([, ])])
|
---|
1897 |
|
---|
1898 |
|
---|
1899 |
|
---|
1900 | # m4_flatten(STRING)
|
---|
1901 | # ------------------
|
---|
1902 | # If STRING contains end of lines, replace them with spaces. If there
|
---|
1903 | # are backslashed end of lines, remove them. This macro is safe with
|
---|
1904 | # active symbols.
|
---|
1905 | # m4_define(active, ACTIVE)
|
---|
1906 | # m4_flatten([active
|
---|
1907 | # act\
|
---|
1908 | # ive])end
|
---|
1909 | # => active activeend
|
---|
1910 | #
|
---|
1911 | # In m4, m4_bpatsubst is expensive, so first check for a newline.
|
---|
1912 | m4_define([m4_flatten],
|
---|
1913 | [m4_if(m4_index([$1], [
|
---|
1914 | ]), [-1], [[$1]],
|
---|
1915 | [m4_translit(m4_bpatsubst([[[$1]]], [\\
|
---|
1916 | ]), [
|
---|
1917 | ], [ ])])])
|
---|
1918 |
|
---|
1919 |
|
---|
1920 | # m4_strip(STRING)
|
---|
1921 | # ----------------
|
---|
1922 | # Expands into STRING with tabs and spaces singled out into a single
|
---|
1923 | # space, and removing leading and trailing spaces.
|
---|
1924 | #
|
---|
1925 | # This macro is robust to active symbols.
|
---|
1926 | # m4_define(active, ACTIVE)
|
---|
1927 | # m4_strip([ active <tab> <tab>active ])end
|
---|
1928 | # => active activeend
|
---|
1929 | #
|
---|
1930 | # First, notice that we guarantee trailing space. Why? Because regular
|
---|
1931 | # expressions are greedy, and `.* ?' would always group the space into the
|
---|
1932 | # .* portion. The algorithm is simpler by avoiding `?' at the end. The
|
---|
1933 | # algorithm correctly strips everything if STRING is just ` '.
|
---|
1934 | #
|
---|
1935 | # Then notice the second pattern: it is in charge of removing the
|
---|
1936 | # leading/trailing spaces. Why not just `[^ ]'? Because they are
|
---|
1937 | # applied to over-quoted strings, i.e. more or less [STRING], due
|
---|
1938 | # to the limitations of m4_bpatsubsts. So the leading space in STRING
|
---|
1939 | # is the *second* character; equally for the trailing space.
|
---|
1940 | m4_define([m4_strip],
|
---|
1941 | [m4_bpatsubsts([$1 ],
|
---|
1942 | [[ ]+], [ ],
|
---|
1943 | [^. ?\(.*\) .$], [[[\1]]])])
|
---|
1944 |
|
---|
1945 |
|
---|
1946 | # m4_normalize(STRING)
|
---|
1947 | # --------------------
|
---|
1948 | # Apply m4_flatten and m4_strip to STRING.
|
---|
1949 | #
|
---|
1950 | # The argument is quoted, so that the macro is robust to active symbols:
|
---|
1951 | #
|
---|
1952 | # m4_define(active, ACTIVE)
|
---|
1953 | # m4_normalize([ act\
|
---|
1954 | # ive
|
---|
1955 | # active ])end
|
---|
1956 | # => active activeend
|
---|
1957 |
|
---|
1958 | m4_define([m4_normalize],
|
---|
1959 | [m4_strip(m4_flatten([$1]))])
|
---|
1960 |
|
---|
1961 |
|
---|
1962 |
|
---|
1963 | # m4_join(SEP, ARG1, ARG2...)
|
---|
1964 | # ---------------------------
|
---|
1965 | # Produce ARG1SEPARG2...SEPARGn. Avoid back-to-back SEP when a given ARG
|
---|
1966 | # is the empty string. No expansion is performed on SEP or ARGs.
|
---|
1967 | #
|
---|
1968 | # Since the number of arguments to join can be arbitrarily long, we
|
---|
1969 | # want to avoid having more than one $@ in the macro definition;
|
---|
1970 | # otherwise, the expansion would require twice the memory of the already
|
---|
1971 | # long list. Hence, m4_join merely looks for the first non-empty element,
|
---|
1972 | # and outputs just that element; while _m4_join looks for all non-empty
|
---|
1973 | # elements, and outputs them following a separator. The final trick to
|
---|
1974 | # note is that we decide between recursing with $0 or _$0 based on the
|
---|
1975 | # nested m4_if ending with `_'.
|
---|
1976 | #
|
---|
1977 | # Please keep foreach.m4 in sync with any adjustments made here.
|
---|
1978 | m4_define([m4_join],
|
---|
1979 | [m4_if([$#], [1], [],
|
---|
1980 | [$#], [2], [[$2]],
|
---|
1981 | [m4_if([$2], [], [], [[$2]_])$0([$1], m4_shift2($@))])])
|
---|
1982 | m4_define([_m4_join],
|
---|
1983 | [m4_if([$#$2], [2], [],
|
---|
1984 | [m4_if([$2], [], [], [[$1$2]])$0([$1], m4_shift2($@))])])
|
---|
1985 |
|
---|
1986 | # m4_joinall(SEP, ARG1, ARG2...)
|
---|
1987 | # ------------------------------
|
---|
1988 | # Produce ARG1SEPARG2...SEPARGn. An empty ARG results in back-to-back SEP.
|
---|
1989 | # No expansion is performed on SEP or ARGs.
|
---|
1990 | #
|
---|
1991 | # Please keep foreach.m4 in sync with any adjustments made here.
|
---|
1992 | m4_define([m4_joinall], [[$2]_$0([$1], m4_shift($@))])
|
---|
1993 | m4_define([_m4_joinall],
|
---|
1994 | [m4_if([$#], [2], [], [[$1$3]$0([$1], m4_shift2($@))])])
|
---|
1995 |
|
---|
1996 | # m4_combine([SEPARATOR], PREFIX-LIST, [INFIX], SUFFIX...)
|
---|
1997 | # --------------------------------------------------------
|
---|
1998 | # Produce the pairwise combination of every element in the quoted,
|
---|
1999 | # comma-separated PREFIX-LIST with every element from the SUFFIX arguments.
|
---|
2000 | # Each pair is joined with INFIX, and pairs are separated by SEPARATOR.
|
---|
2001 | # No expansion occurs on SEPARATOR, INFIX, or elements of either list.
|
---|
2002 | #
|
---|
2003 | # For example:
|
---|
2004 | # m4_combine([, ], [[a], [b], [c]], [-], [1], [2], [3])
|
---|
2005 | # => a-1, a-2, a-3, b-1, b-2, b-3, c-1, c-2, c-3
|
---|
2006 | #
|
---|
2007 | # In order to have the correct number of SEPARATORs, we use a temporary
|
---|
2008 | # variable that redefines itself after the first use. We must use defn
|
---|
2009 | # rather than overquoting in case PREFIX or SUFFIX contains $1, but use
|
---|
2010 | # _m4_defn for speed. Likewise, we compute the m4_shift3 only once,
|
---|
2011 | # rather than in each iteration of the outer m4_foreach.
|
---|
2012 | m4_define([m4_combine],
|
---|
2013 | [m4_if(m4_eval([$# > 3]), [1],
|
---|
2014 | [m4_pushdef([m4_Separator], [m4_define([m4_Separator],
|
---|
2015 | _m4_defn([m4_echo]))])]]dnl
|
---|
2016 | [[m4_foreach([m4_Prefix], [$2],
|
---|
2017 | [m4_foreach([m4_Suffix], ]m4_dquote(m4_dquote(m4_shift3($@)))[,
|
---|
2018 | [m4_Separator([$1])[]_m4_defn([m4_Prefix])[$3]_m4_defn(
|
---|
2019 | [m4_Suffix])])])]]dnl
|
---|
2020 | [[_m4_popdef([m4_Separator])])])
|
---|
2021 |
|
---|
2022 |
|
---|
2023 | # m4_append(MACRO-NAME, STRING, [SEPARATOR])
|
---|
2024 | # ------------------------------------------
|
---|
2025 | # Redefine MACRO-NAME to hold its former content plus `SEPARATOR`'STRING'
|
---|
2026 | # at the end. It is valid to use this macro with MACRO-NAME undefined,
|
---|
2027 | # in which case no SEPARATOR is added. Be aware that the criterion is
|
---|
2028 | # `not being defined', and not `not being empty'.
|
---|
2029 | #
|
---|
2030 | # Note that neither STRING nor SEPARATOR are expanded here; rather, when
|
---|
2031 | # you expand MACRO-NAME, they will be expanded at that point in time.
|
---|
2032 | #
|
---|
2033 | # This macro is robust to active symbols. It can be used to grow
|
---|
2034 | # strings.
|
---|
2035 | #
|
---|
2036 | # | m4_define(active, ACTIVE)dnl
|
---|
2037 | # | m4_append([sentence], [This is an])dnl
|
---|
2038 | # | m4_append([sentence], [ active ])dnl
|
---|
2039 | # | m4_append([sentence], [symbol.])dnl
|
---|
2040 | # | sentence
|
---|
2041 | # | m4_undefine([active])dnl
|
---|
2042 | # | sentence
|
---|
2043 | # => This is an ACTIVE symbol.
|
---|
2044 | # => This is an active symbol.
|
---|
2045 | #
|
---|
2046 | # It can be used to define hooks.
|
---|
2047 | #
|
---|
2048 | # | m4_define(active, ACTIVE)dnl
|
---|
2049 | # | m4_append([hooks], [m4_define([act1], [act2])])dnl
|
---|
2050 | # | m4_append([hooks], [m4_define([act2], [active])])dnl
|
---|
2051 | # | m4_undefine([active])dnl
|
---|
2052 | # | act1
|
---|
2053 | # | hooks
|
---|
2054 | # | act1
|
---|
2055 | # => act1
|
---|
2056 | # =>
|
---|
2057 | # => active
|
---|
2058 | #
|
---|
2059 | # It can also be used to create lists, although this particular usage was
|
---|
2060 | # broken prior to autoconf 2.62.
|
---|
2061 | # | m4_append([list], [one], [, ])dnl
|
---|
2062 | # | m4_append([list], [two], [, ])dnl
|
---|
2063 | # | m4_append([list], [three], [, ])dnl
|
---|
2064 | # | list
|
---|
2065 | # | m4_dquote(list)
|
---|
2066 | # => one, two, three
|
---|
2067 | # => [one],[two],[three]
|
---|
2068 | #
|
---|
2069 | # Note that m4_append can benefit from amortized O(n) m4 behavior, if
|
---|
2070 | # the underlying m4 implementation is smart enough to avoid copying existing
|
---|
2071 | # contents when enlarging a macro's definition into any pre-allocated storage
|
---|
2072 | # (m4 1.4.x unfortunately does not implement this optimization). We do
|
---|
2073 | # not implement m4_prepend, since it is inherently O(n^2) (pre-allocated
|
---|
2074 | # storage only occurs at the end of a macro, so the existing contents must
|
---|
2075 | # always be moved).
|
---|
2076 | #
|
---|
2077 | # Use _m4_defn for speed.
|
---|
2078 | m4_define([m4_append],
|
---|
2079 | [m4_define([$1], m4_ifdef([$1], [_m4_defn([$1])[$3]])[$2])])
|
---|
2080 |
|
---|
2081 |
|
---|
2082 | # m4_append_uniq(MACRO-NAME, STRING, [SEPARATOR], [IF-UNIQ], [IF-DUP])
|
---|
2083 | # --------------------------------------------------------------------
|
---|
2084 | # Like `m4_append', but append only if not yet present. Additionally,
|
---|
2085 | # expand IF-UNIQ if STRING was appended, or IF-DUP if STRING was already
|
---|
2086 | # present. Also, warn if SEPARATOR is not empty and occurs within STRING,
|
---|
2087 | # as the algorithm no longer guarantees uniqueness.
|
---|
2088 | #
|
---|
2089 | # Note that while m4_append can be O(n) (depending on the quality of the
|
---|
2090 | # underlying M4 implementation), m4_append_uniq is inherently O(n^2)
|
---|
2091 | # because each append operation searches the entire string.
|
---|
2092 | m4_define([m4_append_uniq],
|
---|
2093 | [m4_ifval([$3], [m4_if(m4_index([$2], [$3]), [-1], [],
|
---|
2094 | [m4_warn([syntax],
|
---|
2095 | [$0: `$2' contains `$3'])])])_$0($@)])
|
---|
2096 | m4_define([_m4_append_uniq],
|
---|
2097 | [m4_ifdef([$1],
|
---|
2098 | [m4_if(m4_index([$3]_m4_defn([$1])[$3], [$3$2$3]), [-1],
|
---|
2099 | [m4_append([$1], [$2], [$3])$4], [$5])],
|
---|
2100 | [m4_define([$1], [$2])$4])])
|
---|
2101 |
|
---|
2102 | # m4_append_uniq_w(MACRO-NAME, STRINGS)
|
---|
2103 | # -------------------------------------
|
---|
2104 | # For each of the words in the whitespace separated list STRINGS, append
|
---|
2105 | # only the unique strings to the definition of MACRO-NAME.
|
---|
2106 | #
|
---|
2107 | # Use _m4_defn for speed.
|
---|
2108 | m4_define([m4_append_uniq_w],
|
---|
2109 | [m4_foreach_w([m4_Word], [$2],
|
---|
2110 | [_m4_append_uniq([$1], _m4_defn([m4_Word]), [ ])])])
|
---|
2111 |
|
---|
2112 |
|
---|
2113 | # m4_text_wrap(STRING, [PREFIX], [FIRST-PREFIX], [WIDTH])
|
---|
2114 | # -------------------------------------------------------
|
---|
2115 | # Expands into STRING wrapped to hold in WIDTH columns (default = 79).
|
---|
2116 | # If PREFIX is given, each line is prefixed with it. If FIRST-PREFIX is
|
---|
2117 | # specified, then the first line is prefixed with it. As a special case,
|
---|
2118 | # if the length of FIRST-PREFIX is greater than that of PREFIX, then
|
---|
2119 | # FIRST-PREFIX will be left alone on the first line.
|
---|
2120 | #
|
---|
2121 | # No expansion occurs on the contents STRING, PREFIX, or FIRST-PREFIX,
|
---|
2122 | # although quadrigraphs are correctly recognized.
|
---|
2123 | #
|
---|
2124 | # Typical outputs are:
|
---|
2125 | #
|
---|
2126 | # m4_text_wrap([Short string */], [ ], [/* ], 20)
|
---|
2127 | # => /* Short string */
|
---|
2128 | #
|
---|
2129 | # m4_text_wrap([Much longer string */], [ ], [/* ], 20)
|
---|
2130 | # => /* Much longer
|
---|
2131 | # => string */
|
---|
2132 | #
|
---|
2133 | # m4_text_wrap([Short doc.], [ ], [ --short ], 30)
|
---|
2134 | # => --short Short doc.
|
---|
2135 | #
|
---|
2136 | # m4_text_wrap([Short doc.], [ ], [ --too-wide ], 30)
|
---|
2137 | # => --too-wide
|
---|
2138 | # => Short doc.
|
---|
2139 | #
|
---|
2140 | # m4_text_wrap([Super long documentation.], [ ], [ --too-wide ], 30)
|
---|
2141 | # => --too-wide
|
---|
2142 | # => Super long
|
---|
2143 | # => documentation.
|
---|
2144 | #
|
---|
2145 | # FIXME: there is no checking of a longer PREFIX than WIDTH, but do
|
---|
2146 | # we really want to bother with people trying each single corner
|
---|
2147 | # of a software?
|
---|
2148 | #
|
---|
2149 | # This macro does not leave a trailing space behind the last word of a line,
|
---|
2150 | # which complicates it a bit. The algorithm is otherwise stupid and simple:
|
---|
2151 | # all the words are preceded by m4_Separator which is defined to empty for
|
---|
2152 | # the first word, and then ` ' (single space) for all the others.
|
---|
2153 | #
|
---|
2154 | # The algorithm uses a helper that uses $2 through $4 directly, rather than
|
---|
2155 | # using local variables, to avoid m4_defn overhead, or expansion swallowing
|
---|
2156 | # any $. It also bypasses m4_popdef overhead with _m4_popdef since no user
|
---|
2157 | # macro expansion occurs in the meantime. Also, the definition is written
|
---|
2158 | # with m4_do, to avoid time wasted on dnl during expansion (since this is
|
---|
2159 | # already a time-consuming macro).
|
---|
2160 | m4_define([m4_text_wrap],
|
---|
2161 | [_$0([$1], [$2], m4_if([$3], [], [[$2]], [[$3]]),
|
---|
2162 | m4_if([$4], [], [79], [[$4]]))])
|
---|
2163 | m4_define([_m4_text_wrap],
|
---|
2164 | m4_do(dnl set up local variables, to avoid repeated calculations
|
---|
2165 | [[m4_pushdef([m4_Indent], m4_qlen([$2]))]],
|
---|
2166 | [[m4_pushdef([m4_Cursor], m4_qlen([$3]))]],
|
---|
2167 | [[m4_pushdef([m4_Separator], [m4_define([m4_Separator], [ ])])]],
|
---|
2168 | dnl expand the first prefix, then check its length vs. regular prefix
|
---|
2169 | dnl same length: nothing special
|
---|
2170 | dnl prefix1 longer: output on line by itself, and reset cursor
|
---|
2171 | dnl prefix1 shorter: pad to length of prefix, and reset cursor
|
---|
2172 | [[[$3]m4_cond([m4_Cursor], m4_Indent, [],
|
---|
2173 | [m4_eval(m4_Cursor > m4_Indent)], [1], [
|
---|
2174 | [$2]m4_define([m4_Cursor], m4_Indent)],
|
---|
2175 | [m4_format([%*s], m4_max([0],
|
---|
2176 | m4_eval(m4_Indent - m4_Cursor)), [])m4_define([m4_Cursor], m4_Indent)])]],
|
---|
2177 | dnl now, for each word, compute the curser after the word is output, then
|
---|
2178 | dnl check if the cursor would exceed the wrap column
|
---|
2179 | dnl if so, reset cursor, and insert newline and prefix
|
---|
2180 | dnl if not, insert the separator (usually a space)
|
---|
2181 | dnl either way, insert the word
|
---|
2182 | [[m4_foreach_w([m4_Word], [$1],
|
---|
2183 | [m4_define([m4_Cursor],
|
---|
2184 | m4_eval(m4_Cursor + m4_qlen(_m4_defn([m4_Word]))
|
---|
2185 | + 1))m4_if(m4_eval(m4_Cursor > ([$4])),
|
---|
2186 | [1], [m4_define([m4_Cursor],
|
---|
2187 | m4_eval(m4_Indent + m4_qlen(_m4_defn([m4_Word])) + 1))
|
---|
2188 | [$2]],
|
---|
2189 | [m4_Separator[]])_m4_defn([m4_Word])])]],
|
---|
2190 | dnl finally, clean up the local variabls
|
---|
2191 | [[_m4_popdef([m4_Separator], [m4_Cursor], [m4_Indent])]]))
|
---|
2192 |
|
---|
2193 |
|
---|
2194 | # m4_text_box(MESSAGE, [FRAME-CHARACTER = `-'])
|
---|
2195 | # ---------------------------------------------
|
---|
2196 | # Turn MESSAGE into:
|
---|
2197 | # ## ------- ##
|
---|
2198 | # ## MESSAGE ##
|
---|
2199 | # ## ------- ##
|
---|
2200 | # using FRAME-CHARACTER in the border.
|
---|
2201 | m4_define([m4_text_box],
|
---|
2202 | [m4_pushdef([m4_Border],
|
---|
2203 | m4_translit(m4_format([%*s], m4_qlen(m4_expand([$1])), []),
|
---|
2204 | [ ], m4_if([$2], [], [[-]], [[$2]])))dnl
|
---|
2205 | @%:@@%:@ m4_Border @%:@@%:@
|
---|
2206 | @%:@@%:@ $1 @%:@@%:@
|
---|
2207 | @%:@@%:@ m4_Border @%:@@%:@_m4_popdef([m4_Border])dnl
|
---|
2208 | ])
|
---|
2209 |
|
---|
2210 |
|
---|
2211 | # m4_qlen(STRING)
|
---|
2212 | # ---------------
|
---|
2213 | # Expands to the length of STRING after autom4te converts all quadrigraphs.
|
---|
2214 | #
|
---|
2215 | # Avoid bpatsubsts for the common case of no quadrigraphs.
|
---|
2216 | m4_define([m4_qlen],
|
---|
2217 | [m4_if(m4_index([$1], [@]), [-1], [m4_len([$1])],
|
---|
2218 | [m4_len(m4_bpatsubst([[$1]],
|
---|
2219 | [@\(\(<:\|:>\|S|\|%:\|\{:\|:\}\)\(@\)\|&t@\)],
|
---|
2220 | [\3]))])])
|
---|
2221 |
|
---|
2222 |
|
---|
2223 | # m4_qdelta(STRING)
|
---|
2224 | # -----------------
|
---|
2225 | # Expands to the net change in the length of STRING from autom4te converting the
|
---|
2226 | # quadrigraphs in STRING. This number is always negative or zero.
|
---|
2227 | m4_define([m4_qdelta],
|
---|
2228 | [m4_eval(m4_qlen([$1]) - m4_len([$1]))])
|
---|
2229 |
|
---|
2230 |
|
---|
2231 |
|
---|
2232 | ## ----------------------- ##
|
---|
2233 | ## 13. Number processing. ##
|
---|
2234 | ## ----------------------- ##
|
---|
2235 |
|
---|
2236 | # m4_cmp(A, B)
|
---|
2237 | # ------------
|
---|
2238 | # Compare two integer expressions.
|
---|
2239 | # A < B -> -1
|
---|
2240 | # A = B -> 0
|
---|
2241 | # A > B -> 1
|
---|
2242 | m4_define([m4_cmp],
|
---|
2243 | [m4_eval((([$1]) > ([$2])) - (([$1]) < ([$2])))])
|
---|
2244 |
|
---|
2245 |
|
---|
2246 | # m4_list_cmp(A, B)
|
---|
2247 | # -----------------
|
---|
2248 | #
|
---|
2249 | # Compare the two lists of integer expressions A and B. For instance:
|
---|
2250 | # m4_list_cmp([1, 0], [1]) -> 0
|
---|
2251 | # m4_list_cmp([1, 0], [1, 0]) -> 0
|
---|
2252 | # m4_list_cmp([1, 2], [1, 0]) -> 1
|
---|
2253 | # m4_list_cmp([1, 2, 3], [1, 2]) -> 1
|
---|
2254 | # m4_list_cmp([1, 2, -3], [1, 2]) -> -1
|
---|
2255 | # m4_list_cmp([1, 0], [1, 2]) -> -1
|
---|
2256 | # m4_list_cmp([1], [1, 2]) -> -1
|
---|
2257 | # m4_define([xa], [oops])dnl
|
---|
2258 | # m4_list_cmp([[0xa]], [5+5]) -> 0
|
---|
2259 | #
|
---|
2260 | # Rather than face the overhead of m4_case, we use a helper function whose
|
---|
2261 | # expansion includes the name of the macro to invoke on the tail, either
|
---|
2262 | # m4_ignore or m4_unquote. This is particularly useful when comparing
|
---|
2263 | # long lists, since less text is being expanded for deciding when to end
|
---|
2264 | # recursion. The recursion is between a pair of macros that alternate
|
---|
2265 | # which list is trimmed by one element; this is more efficient than
|
---|
2266 | # calling m4_cdr on both lists from a single macro. Guarantee exactly
|
---|
2267 | # one expansion of both lists' side effects.
|
---|
2268 | #
|
---|
2269 | # Please keep foreach.m4 in sync with any adjustments made here.
|
---|
2270 | m4_define([m4_list_cmp],
|
---|
2271 | [_$0_raw(m4_dquote($1), m4_dquote($2))])
|
---|
2272 |
|
---|
2273 | m4_define([_m4_list_cmp_raw],
|
---|
2274 | [m4_if([$1], [$2], [0], [_m4_list_cmp_1([$1], $2)])])
|
---|
2275 |
|
---|
2276 | m4_define([_m4_list_cmp],
|
---|
2277 | [m4_if([$1], [], [0m4_ignore], [$2], [0], [m4_unquote], [$2m4_ignore])])
|
---|
2278 |
|
---|
2279 | m4_define([_m4_list_cmp_1],
|
---|
2280 | [_m4_list_cmp_2([$2], [m4_shift2($@)], $1)])
|
---|
2281 |
|
---|
2282 | m4_define([_m4_list_cmp_2],
|
---|
2283 | [_m4_list_cmp([$1$3], m4_cmp([$3+0], [$1+0]))(
|
---|
2284 | [_m4_list_cmp_1(m4_dquote(m4_shift3($@)), $2)])])
|
---|
2285 |
|
---|
2286 | # m4_max(EXPR, ...)
|
---|
2287 | # m4_min(EXPR, ...)
|
---|
2288 | # -----------------
|
---|
2289 | # Return the decimal value of the maximum (or minimum) in a series of
|
---|
2290 | # integer expressions.
|
---|
2291 | #
|
---|
2292 | # M4 1.4.x doesn't provide ?:. Hence this huge m4_eval. Avoid m4_eval
|
---|
2293 | # if both arguments are identical, but be aware of m4_max(0xa, 10) (hence
|
---|
2294 | # the use of <=, not just <, in the second multiply).
|
---|
2295 | #
|
---|
2296 | # Please keep foreach.m4 in sync with any adjustments made here.
|
---|
2297 | m4_define([m4_max],
|
---|
2298 | [m4_if([$#], [0], [m4_fatal([too few arguments to $0])],
|
---|
2299 | [$#], [1], [m4_eval([$1])],
|
---|
2300 | [$#$1], [2$2], [m4_eval([$1])],
|
---|
2301 | [$#], [2], [_$0($@)],
|
---|
2302 | [_m4_minmax([_$0], $@)])])
|
---|
2303 |
|
---|
2304 | m4_define([_m4_max],
|
---|
2305 | [m4_eval((([$1]) > ([$2])) * ([$1]) + (([$1]) <= ([$2])) * ([$2]))])
|
---|
2306 |
|
---|
2307 | m4_define([m4_min],
|
---|
2308 | [m4_if([$#], [0], [m4_fatal([too few arguments to $0])],
|
---|
2309 | [$#], [1], [m4_eval([$1])],
|
---|
2310 | [$#$1], [2$2], [m4_eval([$1])],
|
---|
2311 | [$#], [2], [_$0($@)],
|
---|
2312 | [_m4_minmax([_$0], $@)])])
|
---|
2313 |
|
---|
2314 | m4_define([_m4_min],
|
---|
2315 | [m4_eval((([$1]) < ([$2])) * ([$1]) + (([$1]) >= ([$2])) * ([$2]))])
|
---|
2316 |
|
---|
2317 | # _m4_minmax(METHOD, ARG1, ARG2...)
|
---|
2318 | # ---------------------------------
|
---|
2319 | # Common recursion code for m4_max and m4_min. METHOD must be _m4_max
|
---|
2320 | # or _m4_min, and there must be at least two arguments to combine.
|
---|
2321 | #
|
---|
2322 | # Please keep foreach.m4 in sync with any adjustments made here.
|
---|
2323 | m4_define([_m4_minmax],
|
---|
2324 | [m4_if([$#], [3], [$1([$2], [$3])],
|
---|
2325 | [$0([$1], $1([$2], [$3]), m4_shift3($@))])])
|
---|
2326 |
|
---|
2327 |
|
---|
2328 | # m4_sign(A)
|
---|
2329 | # ----------
|
---|
2330 | # The sign of the integer expression A.
|
---|
2331 | m4_define([m4_sign],
|
---|
2332 | [m4_eval((([$1]) > 0) - (([$1]) < 0))])
|
---|
2333 |
|
---|
2334 |
|
---|
2335 |
|
---|
2336 | ## ------------------------ ##
|
---|
2337 | ## 14. Version processing. ##
|
---|
2338 | ## ------------------------ ##
|
---|
2339 |
|
---|
2340 |
|
---|
2341 | # m4_version_unletter(VERSION)
|
---|
2342 | # ----------------------------
|
---|
2343 | # Normalize beta version numbers with letters to numeric expressions, which
|
---|
2344 | # can then be handed to m4_eval for the purpose of comparison.
|
---|
2345 | #
|
---|
2346 | # Nl -> (N+1).-1.(l#)
|
---|
2347 | #
|
---|
2348 | # for example:
|
---|
2349 | # [2.14a] -> [2.14+1.-1.[0r36:a]] -> 2.15.-1.10
|
---|
2350 | # [2.14b] -> [2.15+1.-1.[0r36:b]] -> 2.15.-1.11
|
---|
2351 | # [2.61aa.b] -> [2.61+1.-1.[0r36:aa],+1.-1.[0r36:b]] -> 2.62.-1.370.1.-1.11
|
---|
2352 | #
|
---|
2353 | # This macro expects reasonable version numbers, but can handle double
|
---|
2354 | # letters and does not expand any macros. Original version strings can
|
---|
2355 | # use both `.' and `-' separators.
|
---|
2356 | #
|
---|
2357 | # Inline constant expansions, to avoid m4_defn overhead.
|
---|
2358 | # _m4_version_unletter is the real workhorse used by m4_version_compare,
|
---|
2359 | # but since [0r36:a] is less readable than 10, we provide a wrapper for
|
---|
2360 | # human use.
|
---|
2361 | m4_define([m4_version_unletter],
|
---|
2362 | [m4_map_sep([m4_eval], [.],
|
---|
2363 | m4_dquote(m4_dquote_elt(m4_unquote(_$0([$1])))))])
|
---|
2364 | m4_define([_m4_version_unletter],
|
---|
2365 | [m4_bpatsubst(m4_translit([[[$1]]], [.-], [,,]),]dnl
|
---|
2366 | m4_dquote(m4_dquote(m4_defn([m4_cr_Letters])))[[+],
|
---|
2367 | [+1,-1,[0r36:\&]])])
|
---|
2368 |
|
---|
2369 |
|
---|
2370 | # m4_version_compare(VERSION-1, VERSION-2)
|
---|
2371 | # ----------------------------------------
|
---|
2372 | # Compare the two version numbers and expand into
|
---|
2373 | # -1 if VERSION-1 < VERSION-2
|
---|
2374 | # 0 if =
|
---|
2375 | # 1 if >
|
---|
2376 | #
|
---|
2377 | # Since _m4_version_unletter does not output side effects, we can
|
---|
2378 | # safely bypass the overhead of m4_version_cmp.
|
---|
2379 | m4_define([m4_version_compare],
|
---|
2380 | [_m4_list_cmp_raw(_m4_version_unletter([$1]), _m4_version_unletter([$2]))])
|
---|
2381 |
|
---|
2382 |
|
---|
2383 | # m4_PACKAGE_NAME
|
---|
2384 | # m4_PACKAGE_TARNAME
|
---|
2385 | # m4_PACKAGE_VERSION
|
---|
2386 | # m4_PACKAGE_STRING
|
---|
2387 | # m4_PACKAGE_BUGREPORT
|
---|
2388 | # --------------------
|
---|
2389 | # If m4sugar/version.m4 is present, then define version strings. This
|
---|
2390 | # file is optional, provided by Autoconf but absent in Bison.
|
---|
2391 | m4_sinclude([m4sugar/version.m4])
|
---|
2392 |
|
---|
2393 |
|
---|
2394 | # m4_version_prereq(VERSION, [IF-OK], [IF-NOT = FAIL])
|
---|
2395 | # ----------------------------------------------------
|
---|
2396 | # Check this Autoconf version against VERSION.
|
---|
2397 | m4_define([m4_version_prereq],
|
---|
2398 | m4_ifdef([m4_PACKAGE_VERSION],
|
---|
2399 | [[m4_if(m4_version_compare(]m4_dquote(m4_defn([m4_PACKAGE_VERSION]))[, [$1]),
|
---|
2400 | [-1],
|
---|
2401 | [m4_default([$3],
|
---|
2402 | [m4_fatal([Autoconf version $1 or higher is required],
|
---|
2403 | [63])])],
|
---|
2404 | [$2])]],
|
---|
2405 | [[m4_fatal([m4sugar/version.m4 not found])]]))
|
---|
2406 |
|
---|
2407 |
|
---|
2408 | ## ------------------ ##
|
---|
2409 | ## 15. Set handling. ##
|
---|
2410 | ## ------------------ ##
|
---|
2411 |
|
---|
2412 | # Autoconf likes to create arbitrarily large sets; for example, as of
|
---|
2413 | # this writing, the configure.ac for coreutils tracks a set of more
|
---|
2414 | # than 400 AC_SUBST. How do we track all of these set members,
|
---|
2415 | # without introducing duplicates? We could use m4_append_uniq, with
|
---|
2416 | # the set NAME residing in the contents of the macro NAME.
|
---|
2417 | # Unfortunately, m4_append_uniq is quadratic for set creation, because
|
---|
2418 | # it costs O(n) to search the string for each of O(n) insertions; not
|
---|
2419 | # to mention that with m4 1.4.x, even using m4_append is slow, costing
|
---|
2420 | # O(n) rather than O(1) per insertion. Other set operations, not used
|
---|
2421 | # by Autoconf but still possible by manipulation of the definition
|
---|
2422 | # tracked in macro NAME, include O(n) deletion of one element and O(n)
|
---|
2423 | # computation of set size. Because the set is exposed to the user via
|
---|
2424 | # the definition of a single macro, we cannot cache any data about the
|
---|
2425 | # set without risking the cache being invalidated by the user
|
---|
2426 | # redefining NAME.
|
---|
2427 | #
|
---|
2428 | # Can we do better? Yes, because m4 gives us an O(1) search function
|
---|
2429 | # for free: ifdef. Additionally, even m4 1.4.x gives us an O(1)
|
---|
2430 | # insert operation for free: pushdef. But to use these, we must
|
---|
2431 | # represent the set via a group of macros; to keep the set consistent,
|
---|
2432 | # we must hide the set so that the user can only manipulate it through
|
---|
2433 | # accessor macros. The contents of the set are maintained through two
|
---|
2434 | # access points; _m4_set([name]) is a pushdef stack of values in the
|
---|
2435 | # set, useful for O(n) traversal of the set contents; while the
|
---|
2436 | # existence of _m4_set([name],value) with no particular value is
|
---|
2437 | # useful for O(1) querying of set membership. And since the user
|
---|
2438 | # cannot externally manipulate the set, we are free to add additional
|
---|
2439 | # caching macros for other performance improvements. Deletion can be
|
---|
2440 | # O(1) per element rather than O(n), by reworking the definition of
|
---|
2441 | # _m4_set([name],value) to be 0 or 1 based on current membership, and
|
---|
2442 | # adding _m4_set_cleanup(name) to defer the O(n) cleanup of
|
---|
2443 | # _m4_set([name]) until we have another reason to do an O(n)
|
---|
2444 | # traversal. The existence of _m4_set_cleanup(name) can then be used
|
---|
2445 | # elsewhere to determine if we must dereference _m4_set([name],value),
|
---|
2446 | # or assume that definition implies set membership. Finally, size can
|
---|
2447 | # be tracked in an O(1) fashion with _m4_set_size(name).
|
---|
2448 | #
|
---|
2449 | # The quoting in _m4_set([name],value) is chosen so that there is no
|
---|
2450 | # ambiguity with a set whose name contains a comma, and so that we can
|
---|
2451 | # supply the value via _m4_defn([_m4_set([name])]) without needing any
|
---|
2452 | # quote manipulation.
|
---|
2453 |
|
---|
2454 | # m4_set_add(SET, VALUE, [IF-UNIQ], [IF-DUP])
|
---|
2455 | # -------------------------------------------
|
---|
2456 | # Add VALUE as an element of SET. Expand IF-UNIQ on the first
|
---|
2457 | # addition, and IF-DUP if it is already in the set. Addition of one
|
---|
2458 | # element is O(1), such that overall set creation is O(n).
|
---|
2459 | #
|
---|
2460 | # We do not want to add a duplicate for a previously deleted but
|
---|
2461 | # unpruned element, but it is just as easy to check existence directly
|
---|
2462 | # as it is to query _m4_set_cleanup($1).
|
---|
2463 | m4_define([m4_set_add],
|
---|
2464 | [m4_ifdef([_m4_set([$1],$2)],
|
---|
2465 | [m4_if(m4_indir([_m4_set([$1],$2)]), [0],
|
---|
2466 | [m4_define([_m4_set([$1],$2)],
|
---|
2467 | [1])_m4_set_size([$1], [m4_incr])$3], [$4])],
|
---|
2468 | [m4_define([_m4_set([$1],$2)],
|
---|
2469 | [1])m4_pushdef([_m4_set([$1])],
|
---|
2470 | [$2])_m4_set_size([$1], [m4_incr])$3])])
|
---|
2471 |
|
---|
2472 | # m4_set_add_all(SET, VALUE...)
|
---|
2473 | # -----------------------------
|
---|
2474 | # Add each VALUE into SET. This is O(n) in the number of VALUEs, and
|
---|
2475 | # can be faster than calling m4_set_add for each VALUE.
|
---|
2476 | #
|
---|
2477 | # Implement two recursion helpers; the check variant is slower but
|
---|
2478 | # handles the case where an element has previously been removed but
|
---|
2479 | # not pruned. The recursion helpers ignore their second argument, so
|
---|
2480 | # that we can use the faster m4_shift2 and 2 arguments, rather than
|
---|
2481 | # _m4_shift2 and one argument, as the signal to end recursion.
|
---|
2482 | #
|
---|
2483 | # Please keep foreach.m4 in sync with any adjustments made here.
|
---|
2484 | m4_define([m4_set_add_all],
|
---|
2485 | [m4_define([_m4_set_size($1)], m4_eval(m4_set_size([$1])
|
---|
2486 | + m4_len(m4_ifdef([_m4_set_cleanup($1)], [_$0_check], [_$0])([$1], $@))))])
|
---|
2487 |
|
---|
2488 | m4_define([_m4_set_add_all],
|
---|
2489 | [m4_if([$#], [2], [],
|
---|
2490 | [m4_ifdef([_m4_set([$1],$3)], [],
|
---|
2491 | [m4_define([_m4_set([$1],$3)], [1])m4_pushdef([_m4_set([$1])],
|
---|
2492 | [$3])-])$0([$1], m4_shift2($@))])])
|
---|
2493 |
|
---|
2494 | m4_define([_m4_set_add_all_check],
|
---|
2495 | [m4_if([$#], [2], [],
|
---|
2496 | [m4_set_add([$1], [$3])$0([$1], m4_shift2($@))])])
|
---|
2497 |
|
---|
2498 | # m4_set_contains(SET, VALUE, [IF-PRESENT], [IF-ABSENT])
|
---|
2499 | # ------------------------------------------------------
|
---|
2500 | # Expand IF-PRESENT if SET contains VALUE, otherwise expand IF-ABSENT.
|
---|
2501 | # This is always O(1).
|
---|
2502 | m4_define([m4_set_contains],
|
---|
2503 | [m4_ifdef([_m4_set_cleanup($1)],
|
---|
2504 | [m4_if(m4_ifdef([_m4_set([$1],$2)],
|
---|
2505 | [m4_indir([_m4_set([$1],$2)])], [0]), [1], [$3], [$4])],
|
---|
2506 | [m4_ifdef([_m4_set([$1],$2)], [$3], [$4])])])
|
---|
2507 |
|
---|
2508 | # m4_set_contents(SET, [SEP])
|
---|
2509 | # ---------------------------
|
---|
2510 | # Expand to a single string containing all the elements in SET,
|
---|
2511 | # separated by SEP, without modifying SET. No provision is made for
|
---|
2512 | # disambiguating set elements that contain non-empty SEP as a
|
---|
2513 | # sub-string, or for recognizing a set that contains only the empty
|
---|
2514 | # string. Order of the output is not guaranteed. If any elements
|
---|
2515 | # have been previously removed from the set, this action will prune
|
---|
2516 | # the unused memory. This is O(n) in the size of the set before
|
---|
2517 | # pruning.
|
---|
2518 | #
|
---|
2519 | # Use _m4_popdef for speed. The existence of _m4_set_cleanup($1)
|
---|
2520 | # determines which version of _1 helper we use.
|
---|
2521 | m4_define([m4_set_contents],
|
---|
2522 | [m4_ifdef([_m4_set_cleanup($1)], [_$0_1c], [_$0_1])([$1])_$0_2([$1],
|
---|
2523 | [_m4_defn([_m4_set_($1)])], [[$2]])])
|
---|
2524 |
|
---|
2525 | # _m4_set_contents_1(SET)
|
---|
2526 | # _m4_set_contents_1c(SET)
|
---|
2527 | # _m4_set_contents_2(SET, SEP, PREP)
|
---|
2528 | # ----------------------------------
|
---|
2529 | # Expand to a list of quoted elements currently in the set, separated
|
---|
2530 | # by SEP, and moving PREP in front of SEP on recursion. To avoid
|
---|
2531 | # nesting limit restrictions, the algorithm must be broken into two
|
---|
2532 | # parts; _1 destructively copies the stack in reverse into
|
---|
2533 | # _m4_set_($1), producing no output; then _2 destructively copies
|
---|
2534 | # _m4_set_($1) back into the stack in reverse. SEP is expanded while
|
---|
2535 | # _m4_set_($1) contains the current element, so a SEP containing
|
---|
2536 | # _m4_defn([_m4_set_($1)]) can produce output in the order the set was
|
---|
2537 | # created. Behavior is undefined if SEP tries to recursively list or
|
---|
2538 | # modify SET in any way other than calling m4_set_remove on the
|
---|
2539 | # current element. Use _1 if all entries in the stack are guaranteed
|
---|
2540 | # to be in the set, and _1c to prune removed entries. Uses _m4_defn
|
---|
2541 | # and _m4_popdef for speed.
|
---|
2542 | m4_define([_m4_set_contents_1],
|
---|
2543 | [m4_ifdef([_m4_set([$1])], [m4_pushdef([_m4_set_($1)],
|
---|
2544 | _m4_defn([_m4_set([$1])]))_m4_popdef([_m4_set([$1])])$0([$1])])])
|
---|
2545 |
|
---|
2546 | m4_define([_m4_set_contents_1c],
|
---|
2547 | [m4_ifdef([_m4_set([$1])],
|
---|
2548 | [m4_set_contains([$1], _m4_defn([_m4_set([$1])]),
|
---|
2549 | [m4_pushdef([_m4_set_($1)], _m4_defn([_m4_set([$1])]))],
|
---|
2550 | [_m4_popdef([_m4_set([$1],]_m4_defn(
|
---|
2551 | [_m4_set([$1])])[)])])_m4_popdef([_m4_set([$1])])$0([$1])],
|
---|
2552 | [_m4_popdef([_m4_set_cleanup($1)])])])
|
---|
2553 |
|
---|
2554 | m4_define([_m4_set_contents_2],
|
---|
2555 | [m4_ifdef([_m4_set_($1)], [m4_pushdef([_m4_set([$1])],
|
---|
2556 | _m4_defn([_m4_set_($1)]))$2[]_m4_popdef([_m4_set_($1)])$0([$1], [$3$2])])])
|
---|
2557 |
|
---|
2558 | # m4_set_delete(SET)
|
---|
2559 | # ------------------
|
---|
2560 | # Delete all elements in SET, and reclaim any memory occupied by the
|
---|
2561 | # set. This is O(n) in the set size.
|
---|
2562 | #
|
---|
2563 | # Use _m4_defn and _m4_popdef for speed.
|
---|
2564 | m4_define([m4_set_delete],
|
---|
2565 | [m4_ifdef([_m4_set([$1])],
|
---|
2566 | [_m4_popdef([_m4_set([$1],]_m4_defn([_m4_set([$1])])[)],
|
---|
2567 | [_m4_set([$1])])$0([$1])],
|
---|
2568 | [m4_ifdef([_m4_set_cleanup($1)],
|
---|
2569 | [_m4_popdef([_m4_set_cleanup($1)])])m4_ifdef(
|
---|
2570 | [_m4_set_size($1)],
|
---|
2571 | [_m4_popdef([_m4_set_size($1)])])])])
|
---|
2572 |
|
---|
2573 | # m4_set_difference(SET1, SET2)
|
---|
2574 | # -----------------------------
|
---|
2575 | # Produce a LIST of quoted elements that occur in SET1 but not SET2.
|
---|
2576 | # Output a comma prior to any elements, to distinguish the empty
|
---|
2577 | # string from no elements. This can be directly used as a series of
|
---|
2578 | # arguments, such as for m4_join, or wrapped inside quotes for use in
|
---|
2579 | # m4_foreach. Order of the output is not guaranteed.
|
---|
2580 | #
|
---|
2581 | # Short-circuit the idempotence relation. Use _m4_defn for speed.
|
---|
2582 | m4_define([m4_set_difference],
|
---|
2583 | [m4_if([$1], [$2], [],
|
---|
2584 | [m4_set_foreach([$1], [_m4_element],
|
---|
2585 | [m4_set_contains([$2], _m4_defn([_m4_element]), [],
|
---|
2586 | [,_m4_defn([_m4_element])])])])])
|
---|
2587 |
|
---|
2588 | # m4_set_dump(SET, [SEP])
|
---|
2589 | # -----------------------
|
---|
2590 | # Expand to a single string containing all the elements in SET,
|
---|
2591 | # separated by SEP, then delete SET. In general, if you only need to
|
---|
2592 | # list the contents once, this is faster than m4_set_contents. No
|
---|
2593 | # provision is made for disambiguating set elements that contain
|
---|
2594 | # non-empty SEP as a sub-string. Order of the output is not
|
---|
2595 | # guaranteed. This is O(n) in the size of the set before pruning.
|
---|
2596 | #
|
---|
2597 | # Use _m4_popdef for speed. Use existence of _m4_set_cleanup($1) to
|
---|
2598 | # decide if more expensive recursion is needed.
|
---|
2599 | m4_define([m4_set_dump],
|
---|
2600 | [m4_ifdef([_m4_set_size($1)],
|
---|
2601 | [_m4_popdef([_m4_set_size($1)])])m4_ifdef([_m4_set_cleanup($1)],
|
---|
2602 | [_$0_check], [_$0])([$1], [], [$2])])
|
---|
2603 |
|
---|
2604 | # _m4_set_dump(SET, SEP, PREP)
|
---|
2605 | # _m4_set_dump_check(SET, SEP, PREP)
|
---|
2606 | # ----------------------------------
|
---|
2607 | # Print SEP and the current element, then delete the element and
|
---|
2608 | # recurse with empty SEP changed to PREP. The check variant checks
|
---|
2609 | # whether the element has been previously removed. Use _m4_defn and
|
---|
2610 | # _m4_popdef for speed.
|
---|
2611 | m4_define([_m4_set_dump],
|
---|
2612 | [m4_ifdef([_m4_set([$1])],
|
---|
2613 | [[$2]_m4_defn([_m4_set([$1])])_m4_popdef([_m4_set([$1],]_m4_defn(
|
---|
2614 | [_m4_set([$1])])[)], [_m4_set([$1])])$0([$1], [$2$3])])])
|
---|
2615 |
|
---|
2616 | m4_define([_m4_set_dump_check],
|
---|
2617 | [m4_ifdef([_m4_set([$1])],
|
---|
2618 | [m4_set_contains([$1], _m4_defn([_m4_set([$1])]),
|
---|
2619 | [[$2]_m4_defn([_m4_set([$1])])])_m4_popdef(
|
---|
2620 | [_m4_set([$1],]_m4_defn([_m4_set([$1])])[)],
|
---|
2621 | [_m4_set([$1])])$0([$1], [$2$3])],
|
---|
2622 | [_m4_popdef([_m4_set_cleanup($1)])])])
|
---|
2623 |
|
---|
2624 | # m4_set_empty(SET, [IF-EMPTY], [IF-ELEMENTS])
|
---|
2625 | # --------------------------------------------
|
---|
2626 | # Expand IF-EMPTY if SET has no elements, otherwise IF-ELEMENTS.
|
---|
2627 | m4_define([m4_set_empty],
|
---|
2628 | [m4_ifdef([_m4_set_size($1)],
|
---|
2629 | [m4_if(m4_indir([_m4_set_size($1)]), [0], [$2], [$3])], [$2])])
|
---|
2630 |
|
---|
2631 | # m4_set_foreach(SET, VAR, ACTION)
|
---|
2632 | # --------------------------------
|
---|
2633 | # For each element of SET, define VAR to the element and expand
|
---|
2634 | # ACTION. ACTION should not recursively list SET's contents, add
|
---|
2635 | # elements to SET, nor delete any element from SET except the one
|
---|
2636 | # currently in VAR. The order that the elements are visited in is not
|
---|
2637 | # guaranteed. This is faster than the corresponding m4_foreach([VAR],
|
---|
2638 | # m4_indir([m4_dquote]m4_set_listc([SET])), [ACTION])
|
---|
2639 | m4_define([m4_set_foreach],
|
---|
2640 | [m4_pushdef([$2])m4_ifdef([_m4_set_cleanup($1)],
|
---|
2641 | [_m4_set_contents_1c], [_m4_set_contents_1])([$1])_m4_set_contents_2([$1],
|
---|
2642 | [m4_define([$2], _m4_defn([_m4_set_($1)]))$3[]])m4_popdef([$2])])
|
---|
2643 |
|
---|
2644 | # m4_set_intersection(SET1, SET2)
|
---|
2645 | # -------------------------------
|
---|
2646 | # Produce a LIST of quoted elements that occur in both SET1 or SET2.
|
---|
2647 | # Output a comma prior to any elements, to distinguish the empty
|
---|
2648 | # string from no elements. This can be directly used as a series of
|
---|
2649 | # arguments, such as for m4_join, or wrapped inside quotes for use in
|
---|
2650 | # m4_foreach. Order of the output is not guaranteed.
|
---|
2651 | #
|
---|
2652 | # Iterate over the smaller set, and short-circuit the idempotence
|
---|
2653 | # relation. Use _m4_defn for speed.
|
---|
2654 | m4_define([m4_set_intersection],
|
---|
2655 | [m4_if([$1], [$2], [m4_set_listc([$1])],
|
---|
2656 | m4_eval(m4_set_size([$2]) < m4_set_size([$1])), [1], [$0([$2], [$1])],
|
---|
2657 | [m4_set_foreach([$1], [_m4_element],
|
---|
2658 | [m4_set_contains([$2], _m4_defn([_m4_element]),
|
---|
2659 | [,_m4_defn([_m4_element])])])])])
|
---|
2660 |
|
---|
2661 | # m4_set_list(SET)
|
---|
2662 | # m4_set_listc(SET)
|
---|
2663 | # -----------------
|
---|
2664 | # Produce a LIST of quoted elements of SET. This can be directly used
|
---|
2665 | # as a series of arguments, such as for m4_join or m4_set_add_all, or
|
---|
2666 | # wrapped inside quotes for use in m4_foreach or m4_map. With
|
---|
2667 | # m4_set_list, there is no way to distinguish an empty set from a set
|
---|
2668 | # containing only the empty string; with m4_set_listc, a leading comma
|
---|
2669 | # is output if there are any elements.
|
---|
2670 | m4_define([m4_set_list],
|
---|
2671 | [m4_ifdef([_m4_set_cleanup($1)], [_m4_set_contents_1c],
|
---|
2672 | [_m4_set_contents_1])([$1])_m4_set_contents_2([$1],
|
---|
2673 | [_m4_defn([_m4_set_($1)])], [,])])
|
---|
2674 |
|
---|
2675 | m4_define([m4_set_listc],
|
---|
2676 | [m4_ifdef([_m4_set_cleanup($1)], [_m4_set_contents_1c],
|
---|
2677 | [_m4_set_contents_1])([$1])_m4_set_contents_2([$1],
|
---|
2678 | [,_m4_defn([_m4_set_($1)])])])
|
---|
2679 |
|
---|
2680 | # m4_set_remove(SET, VALUE, [IF-PRESENT], [IF-ABSENT])
|
---|
2681 | # ----------------------------------------------------
|
---|
2682 | # If VALUE is an element of SET, delete it and expand IF-PRESENT.
|
---|
2683 | # Otherwise expand IF-ABSENT. Deleting a single value is O(1),
|
---|
2684 | # although it leaves memory occupied until the next O(n) traversal of
|
---|
2685 | # the set which will compact the set.
|
---|
2686 | #
|
---|
2687 | # Optimize if the element being removed is the most recently added,
|
---|
2688 | # since defining _m4_set_cleanup($1) slows down so many other macros.
|
---|
2689 | # In particular, this plays well with m4_set_foreach.
|
---|
2690 | m4_define([m4_set_remove],
|
---|
2691 | [m4_set_contains([$1], [$2], [_m4_set_size([$1],
|
---|
2692 | [m4_decr])m4_if(_m4_defn([_m4_set([$1])]), [$2],
|
---|
2693 | [_m4_popdef([_m4_set([$1],$2)], [_m4_set([$1])])],
|
---|
2694 | [m4_define([_m4_set_cleanup($1)])m4_define(
|
---|
2695 | [_m4_set([$1],$2)], [0])])$3], [$4])])
|
---|
2696 |
|
---|
2697 | # m4_set_size(SET)
|
---|
2698 | # ----------------
|
---|
2699 | # Expand to the number of elements currently in SET. This operation
|
---|
2700 | # is O(1), and thus more efficient than m4_count(m4_set_list([SET])).
|
---|
2701 | m4_define([m4_set_size],
|
---|
2702 | [m4_ifdef([_m4_set_size($1)], [m4_indir([_m4_set_size($1)])], [0])])
|
---|
2703 |
|
---|
2704 | # _m4_set_size(SET, ACTION)
|
---|
2705 | # -------------------------
|
---|
2706 | # ACTION must be either m4_incr or m4_decr, and the size of SET is
|
---|
2707 | # changed accordingly. If the set is empty, ACTION must not be
|
---|
2708 | # m4_decr.
|
---|
2709 | m4_define([_m4_set_size],
|
---|
2710 | [m4_define([_m4_set_size($1)],
|
---|
2711 | m4_ifdef([_m4_set_size($1)], [$2(m4_indir([_m4_set_size($1)]))],
|
---|
2712 | [1]))])
|
---|
2713 |
|
---|
2714 | # m4_set_union(SET1, SET2)
|
---|
2715 | # ------------------------
|
---|
2716 | # Produce a LIST of double quoted elements that occur in either SET1
|
---|
2717 | # or SET2, without duplicates. Output a comma prior to any elements,
|
---|
2718 | # to distinguish the empty string from no elements. This can be
|
---|
2719 | # directly used as a series of arguments, such as for m4_join, or
|
---|
2720 | # wrapped inside quotes for use in m4_foreach. Order of the output is
|
---|
2721 | # not guaranteed.
|
---|
2722 | #
|
---|
2723 | # We can rely on the fact that m4_set_listc prunes SET1, so we don't
|
---|
2724 | # need to check _m4_set([$1],element) for 0. Use _m4_defn for speed.
|
---|
2725 | # Short-circuit the idempotence relation.
|
---|
2726 | m4_define([m4_set_union],
|
---|
2727 | [m4_set_listc([$1])m4_if([$1], [$2], [], [m4_set_foreach([$2], [_m4_element],
|
---|
2728 | [m4_ifdef([_m4_set([$1],]_m4_defn([_m4_element])[)], [],
|
---|
2729 | [,_m4_defn([_m4_element])])])])])
|
---|
2730 |
|
---|
2731 |
|
---|
2732 | ## ------------------- ##
|
---|
2733 | ## 16. File handling. ##
|
---|
2734 | ## ------------------- ##
|
---|
2735 |
|
---|
2736 |
|
---|
2737 | # It is a real pity that M4 comes with no macros to bind a diversion
|
---|
2738 | # to a file. So we have to deal without, which makes us a lot more
|
---|
2739 | # fragile than we should.
|
---|
2740 |
|
---|
2741 |
|
---|
2742 | # m4_file_append(FILE-NAME, CONTENT)
|
---|
2743 | # ----------------------------------
|
---|
2744 | m4_define([m4_file_append],
|
---|
2745 | [m4_syscmd([cat >>$1 <<_m4eof
|
---|
2746 | $2
|
---|
2747 | _m4eof
|
---|
2748 | ])
|
---|
2749 | m4_if(m4_sysval, [0], [],
|
---|
2750 | [m4_fatal([$0: cannot write: $1])])])
|
---|
2751 |
|
---|
2752 |
|
---|
2753 |
|
---|
2754 | ## ------------------------ ##
|
---|
2755 | ## 17. Setting M4sugar up. ##
|
---|
2756 | ## ------------------------ ##
|
---|
2757 |
|
---|
2758 |
|
---|
2759 | # m4_init
|
---|
2760 | # -------
|
---|
2761 | # Initialize the m4sugar language.
|
---|
2762 | m4_define([m4_init],
|
---|
2763 | [# All the M4sugar macros start with `m4_', except `dnl' kept as is
|
---|
2764 | # for sake of simplicity.
|
---|
2765 | m4_pattern_forbid([^_?m4_])
|
---|
2766 | m4_pattern_forbid([^dnl$])
|
---|
2767 |
|
---|
2768 | # If __m4_version__ is defined, we assume that we are being run by M4
|
---|
2769 | # 1.6 or newer, and thus that $@ recursion is linear and debugmode(d)
|
---|
2770 | # is available for faster checks of dereferencing undefined macros.
|
---|
2771 | # But if it is missing, we assume we are being run by M4 1.4.x, that
|
---|
2772 | # $@ recursion is quadratic, and that we need foreach-based
|
---|
2773 | # replacement macros. Use the raw builtin to avoid tripping up
|
---|
2774 | # include tracing.
|
---|
2775 | m4_ifdef([__m4_version__],
|
---|
2776 | [m4_debugmode([+d])
|
---|
2777 | m4_copy([_m4_defn], [m4_defn])
|
---|
2778 | m4_copy([_m4_popdef], [m4_popdef])
|
---|
2779 | m4_copy([_m4_undefine], [m4_undefine])],
|
---|
2780 | [m4_builtin([include], [m4sugar/foreach.m4])])
|
---|
2781 |
|
---|
2782 | # _m4_divert_diversion should be defined:
|
---|
2783 | m4_divert_push([KILL])
|
---|
2784 |
|
---|
2785 | # Check the divert push/pop perfect balance.
|
---|
2786 | m4_wrap([m4_divert_pop([])
|
---|
2787 | m4_ifdef([_m4_divert_diversion],
|
---|
2788 | [m4_fatal([$0: unbalanced m4_divert_push:]_m4_divert_n_stack)])[]])
|
---|
2789 | ])
|
---|