[270] | 1 | divert(-1)# -*- Autoconf -*-
|
---|
| 2 | # This file is part of Autoconf.
|
---|
| 3 | # Base M4 layer.
|
---|
| 4 | # Requires GNU M4.
|
---|
| 5 | #
|
---|
| 6 | # Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
|
---|
| 7 | # 2008 Free Software Foundation, Inc.
|
---|
| 8 | #
|
---|
| 9 | # This program is free software: you can redistribute it and/or modify
|
---|
| 10 | # it under the terms of the GNU General Public License as published by
|
---|
| 11 | # the Free Software Foundation, either version 3 of the License, or
|
---|
| 12 | # (at your option) any later version.
|
---|
| 13 | #
|
---|
| 14 | # This program is distributed in the hope that it will be useful,
|
---|
| 15 | # but WITHOUT ANY WARRANTY; without even the implied warranty of
|
---|
| 16 | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
---|
| 17 | # GNU General Public License for more details.
|
---|
| 18 | #
|
---|
| 19 | # You should have received a copy of the GNU General Public License
|
---|
| 20 | # along with this program. If not, see <http://www.gnu.org/licenses/>.
|
---|
| 21 |
|
---|
| 22 | # As a special exception, the Free Software Foundation gives unlimited
|
---|
| 23 | # permission to copy, distribute and modify the configure scripts that
|
---|
| 24 | # are the output of Autoconf. You need not follow the terms of the GNU
|
---|
| 25 | # General Public License when using or distributing such scripts, even
|
---|
| 26 | # though portions of the text of Autoconf appear in them. The GNU
|
---|
| 27 | # General Public License (GPL) does govern all other use of the material
|
---|
| 28 | # that constitutes the Autoconf program.
|
---|
| 29 | #
|
---|
| 30 | # Certain portions of the Autoconf source text are designed to be copied
|
---|
| 31 | # (in certain cases, depending on the input) into the output of
|
---|
| 32 | # Autoconf. We call these the "data" portions. The rest of the Autoconf
|
---|
| 33 | # source text consists of comments plus executable code that decides which
|
---|
| 34 | # of the data portions to output in any given case. We call these
|
---|
| 35 | # comments and executable code the "non-data" portions. Autoconf never
|
---|
| 36 | # copies any of the non-data portions into its output.
|
---|
| 37 | #
|
---|
| 38 | # This special exception to the GPL applies to versions of Autoconf
|
---|
| 39 | # released by the Free Software Foundation. When you make and
|
---|
| 40 | # distribute a modified version of Autoconf, you may extend this special
|
---|
| 41 | # exception to the GPL to apply to your modified version as well, *unless*
|
---|
| 42 | # your modified version has the potential to copy into its output some
|
---|
| 43 | # of the text that was the non-data portion of the version that you started
|
---|
| 44 | # with. (In other words, unless your change moves or copies text from
|
---|
| 45 | # the non-data portions to the data portions.) If your modification has
|
---|
| 46 | # such potential, you must delete any notice of this special exception
|
---|
| 47 | # to the GPL from your modified version.
|
---|
| 48 | #
|
---|
| 49 | # Written by Akim Demaille.
|
---|
| 50 | #
|
---|
| 51 |
|
---|
| 52 | # Set the quotes, whatever the current quoting system.
|
---|
| 53 | changequote()
|
---|
| 54 | changequote([, ])
|
---|
| 55 |
|
---|
| 56 | # Some old m4's don't support m4exit. But they provide
|
---|
| 57 | # equivalent functionality by core dumping because of the
|
---|
| 58 | # long macros we define.
|
---|
| 59 | ifdef([__gnu__], ,
|
---|
| 60 | [errprint(M4sugar requires GNU M4. Install it before installing M4sugar or
|
---|
| 61 | set the M4 environment variable to its absolute file name.)
|
---|
| 62 | m4exit(2)])
|
---|
| 63 |
|
---|
| 64 |
|
---|
| 65 | ## ------------------------------- ##
|
---|
| 66 | ## 1. Simulate --prefix-builtins. ##
|
---|
| 67 | ## ------------------------------- ##
|
---|
| 68 |
|
---|
| 69 | # m4_define
|
---|
| 70 | # m4_defn
|
---|
| 71 | # m4_undefine
|
---|
| 72 | define([m4_define], defn([define]))
|
---|
| 73 | define([m4_defn], defn([defn]))
|
---|
| 74 | define([m4_undefine], defn([undefine]))
|
---|
| 75 |
|
---|
| 76 | m4_undefine([define])
|
---|
| 77 | m4_undefine([defn])
|
---|
| 78 | m4_undefine([undefine])
|
---|
| 79 |
|
---|
| 80 |
|
---|
| 81 | # m4_copy(SRC, DST)
|
---|
| 82 | # -----------------
|
---|
| 83 | # Define DST as the definition of SRC.
|
---|
| 84 | # What's the difference between:
|
---|
| 85 | # 1. m4_copy([from], [to])
|
---|
| 86 | # 2. m4_define([to], [from($@)])
|
---|
| 87 | # Well, obviously 1 is more expensive in space. Maybe 2 is more expensive
|
---|
| 88 | # in time, but because of the space cost of 1, it's not that obvious.
|
---|
| 89 | # Nevertheless, one huge difference is the handling of `$0'. If `from'
|
---|
| 90 | # uses `$0', then with 1, `to''s `$0' is `to', while it is `from' in 2.
|
---|
| 91 | # The user would certainly prefer to see `to'.
|
---|
| 92 | m4_define([m4_copy],
|
---|
| 93 | [m4_define([$2], m4_defn([$1]))])
|
---|
| 94 |
|
---|
| 95 |
|
---|
| 96 | # m4_rename(SRC, DST)
|
---|
| 97 | # -------------------
|
---|
| 98 | # Rename the macro SRC to DST.
|
---|
| 99 | m4_define([m4_rename],
|
---|
| 100 | [m4_copy([$1], [$2])m4_undefine([$1])])
|
---|
| 101 |
|
---|
| 102 |
|
---|
| 103 | # m4_rename_m4(MACRO-NAME)
|
---|
| 104 | # ------------------------
|
---|
| 105 | # Rename MACRO-NAME to m4_MACRO-NAME.
|
---|
| 106 | m4_define([m4_rename_m4],
|
---|
| 107 | [m4_rename([$1], [m4_$1])])
|
---|
| 108 |
|
---|
| 109 |
|
---|
| 110 | # m4_copy_unm4(m4_MACRO-NAME)
|
---|
| 111 | # ---------------------------
|
---|
| 112 | # Copy m4_MACRO-NAME to MACRO-NAME.
|
---|
| 113 | m4_define([m4_copy_unm4],
|
---|
| 114 | [m4_copy([$1], m4_bpatsubst([$1], [^m4_\(.*\)], [[\1]]))])
|
---|
| 115 |
|
---|
| 116 |
|
---|
| 117 | # Some m4 internals have names colliding with tokens we might use.
|
---|
| 118 | # Rename them a` la `m4 --prefix-builtins'. Conditionals first, since
|
---|
| 119 | # some subsequent renames are conditional.
|
---|
| 120 | m4_rename_m4([ifdef])
|
---|
| 121 | m4_rename([ifelse], [m4_if])
|
---|
| 122 |
|
---|
| 123 | m4_rename_m4([builtin])
|
---|
| 124 | m4_rename_m4([changecom])
|
---|
| 125 | m4_rename_m4([changequote])
|
---|
| 126 | m4_ifdef([changeword],dnl conditionally available in 1.4.x
|
---|
| 127 | [m4_undefine([changeword])])
|
---|
| 128 | m4_rename_m4([debugfile])
|
---|
| 129 | m4_rename_m4([debugmode])
|
---|
| 130 | m4_rename_m4([decr])
|
---|
| 131 | m4_undefine([divert])
|
---|
| 132 | m4_rename_m4([divnum])
|
---|
| 133 | m4_rename_m4([dumpdef])
|
---|
| 134 | m4_rename_m4([errprint])
|
---|
| 135 | m4_rename_m4([esyscmd])
|
---|
| 136 | m4_rename_m4([eval])
|
---|
| 137 | m4_rename_m4([format])
|
---|
| 138 | m4_undefine([include])
|
---|
| 139 | m4_rename_m4([incr])
|
---|
| 140 | m4_rename_m4([index])
|
---|
| 141 | m4_rename_m4([indir])
|
---|
| 142 | m4_rename_m4([len])
|
---|
| 143 | m4_rename([m4exit], [m4_exit])
|
---|
| 144 | m4_undefine([m4wrap])
|
---|
| 145 | m4_ifdef([mkstemp],dnl added in M4 1.4.8
|
---|
| 146 | [m4_rename_m4([mkstemp])
|
---|
| 147 | m4_copy([m4_mkstemp], [m4_maketemp])
|
---|
| 148 | m4_undefine([maketemp])],
|
---|
| 149 | [m4_rename_m4([maketemp])
|
---|
| 150 | m4_copy([m4_maketemp], [m4_mkstemp])])
|
---|
| 151 | m4_rename([patsubst], [m4_bpatsubst])
|
---|
| 152 | m4_rename_m4([popdef])
|
---|
| 153 | m4_rename_m4([pushdef])
|
---|
| 154 | m4_rename([regexp], [m4_bregexp])
|
---|
| 155 | m4_rename_m4([shift])
|
---|
| 156 | m4_undefine([sinclude])
|
---|
| 157 | m4_rename_m4([substr])
|
---|
| 158 | m4_ifdef([symbols],dnl present only in alpha-quality 1.4o
|
---|
| 159 | [m4_rename_m4([symbols])])
|
---|
| 160 | m4_rename_m4([syscmd])
|
---|
| 161 | m4_rename_m4([sysval])
|
---|
| 162 | m4_rename_m4([traceoff])
|
---|
| 163 | m4_rename_m4([traceon])
|
---|
| 164 | m4_rename_m4([translit])
|
---|
| 165 | m4_undefine([undivert])
|
---|
| 166 |
|
---|
| 167 |
|
---|
| 168 | ## ------------------- ##
|
---|
| 169 | ## 2. Error messages. ##
|
---|
| 170 | ## ------------------- ##
|
---|
| 171 |
|
---|
| 172 |
|
---|
| 173 | # m4_location
|
---|
| 174 | # -----------
|
---|
| 175 | m4_define([m4_location],
|
---|
| 176 | [__file__:__line__])
|
---|
| 177 |
|
---|
| 178 |
|
---|
| 179 | # m4_errprintn(MSG)
|
---|
| 180 | # -----------------
|
---|
| 181 | # Same as `errprint', but with the missing end of line.
|
---|
| 182 | m4_define([m4_errprintn],
|
---|
| 183 | [m4_errprint([$1
|
---|
| 184 | ])])
|
---|
| 185 |
|
---|
| 186 |
|
---|
| 187 | # m4_warning(MSG)
|
---|
| 188 | # ---------------
|
---|
| 189 | # Warn the user.
|
---|
| 190 | m4_define([m4_warning],
|
---|
| 191 | [m4_errprintn(m4_location[: warning: $1])])
|
---|
| 192 |
|
---|
| 193 |
|
---|
| 194 | # m4_fatal(MSG, [EXIT-STATUS])
|
---|
| 195 | # ----------------------------
|
---|
| 196 | # Fatal the user. :)
|
---|
| 197 | m4_define([m4_fatal],
|
---|
| 198 | [m4_errprintn(m4_location[: error: $1])dnl
|
---|
| 199 | m4_expansion_stack_dump()dnl
|
---|
| 200 | m4_exit(m4_if([$2],, 1, [$2]))])
|
---|
| 201 |
|
---|
| 202 |
|
---|
| 203 | # m4_assert(EXPRESSION, [EXIT-STATUS = 1])
|
---|
| 204 | # ----------------------------------------
|
---|
| 205 | # This macro ensures that EXPRESSION evaluates to true, and exits if
|
---|
| 206 | # EXPRESSION evaluates to false.
|
---|
| 207 | m4_define([m4_assert],
|
---|
| 208 | [m4_if(m4_eval([$1]), 0,
|
---|
| 209 | [m4_fatal([assert failed: $1], [$2])])])
|
---|
| 210 |
|
---|
| 211 |
|
---|
| 212 |
|
---|
| 213 | ## ------------- ##
|
---|
| 214 | ## 3. Warnings. ##
|
---|
| 215 | ## ------------- ##
|
---|
| 216 |
|
---|
| 217 |
|
---|
| 218 | # _m4_warn(CATEGORY, MESSAGE, STACK-TRACE)
|
---|
| 219 | # ----------------------------------------
|
---|
| 220 | # Report a MESSAGE to the user if the CATEGORY of warnings is enabled.
|
---|
| 221 | # This is for traces only.
|
---|
| 222 | # The STACK-TRACE is a \n-separated list of "LOCATION: MESSAGE".
|
---|
| 223 | #
|
---|
| 224 | # Within m4, the macro is a no-op. This macro really matters
|
---|
| 225 | # when autom4te post-processes the trace output.
|
---|
| 226 | m4_define([_m4_warn], [])
|
---|
| 227 |
|
---|
| 228 |
|
---|
| 229 | # m4_warn(CATEGORY, MESSAGE)
|
---|
| 230 | # --------------------------
|
---|
| 231 | # Report a MESSAGE to the user if the CATEGORY of warnings is enabled.
|
---|
| 232 | m4_define([m4_warn],
|
---|
| 233 | [_m4_warn([$1], [$2],
|
---|
| 234 | m4_ifdef([m4_expansion_stack],
|
---|
| 235 | [_m4_defn([m4_expansion_stack])
|
---|
| 236 | m4_location[: the top level]]))dnl
|
---|
| 237 | ])
|
---|
| 238 |
|
---|
| 239 |
|
---|
| 240 |
|
---|
| 241 | ## ------------------- ##
|
---|
| 242 | ## 4. File inclusion. ##
|
---|
| 243 | ## ------------------- ##
|
---|
| 244 |
|
---|
| 245 |
|
---|
| 246 | # We also want to neutralize include (and sinclude for symmetry),
|
---|
| 247 | # but we want to extend them slightly: warn when a file is included
|
---|
| 248 | # several times. This is, in general, a dangerous operation, because
|
---|
| 249 | # too many people forget to quote the first argument of m4_define.
|
---|
| 250 | #
|
---|
| 251 | # For instance in the following case:
|
---|
| 252 | # m4_define(foo, [bar])
|
---|
| 253 | # then a second reading will turn into
|
---|
| 254 | # m4_define(bar, [bar])
|
---|
| 255 | # which is certainly not what was meant.
|
---|
| 256 |
|
---|
| 257 | # m4_include_unique(FILE)
|
---|
| 258 | # -----------------------
|
---|
| 259 | # Declare that the FILE was loading; and warn if it has already
|
---|
| 260 | # been included.
|
---|
| 261 | m4_define([m4_include_unique],
|
---|
| 262 | [m4_ifdef([m4_include($1)],
|
---|
| 263 | [m4_warn([syntax], [file `$1' included several times])])dnl
|
---|
| 264 | m4_define([m4_include($1)])])
|
---|
| 265 |
|
---|
| 266 |
|
---|
| 267 | # m4_include(FILE)
|
---|
| 268 | # ----------------
|
---|
| 269 | # Like the builtin include, but warns against multiple inclusions.
|
---|
| 270 | m4_define([m4_include],
|
---|
| 271 | [m4_include_unique([$1])dnl
|
---|
| 272 | m4_builtin([include], [$1])])
|
---|
| 273 |
|
---|
| 274 |
|
---|
| 275 | # m4_sinclude(FILE)
|
---|
| 276 | # -----------------
|
---|
| 277 | # Like the builtin sinclude, but warns against multiple inclusions.
|
---|
| 278 | m4_define([m4_sinclude],
|
---|
| 279 | [m4_include_unique([$1])dnl
|
---|
| 280 | m4_builtin([sinclude], [$1])])
|
---|
| 281 |
|
---|
| 282 |
|
---|
| 283 |
|
---|
| 284 | ## ------------------------------------ ##
|
---|
| 285 | ## 5. Additional branching constructs. ##
|
---|
| 286 | ## ------------------------------------ ##
|
---|
| 287 |
|
---|
| 288 | # Both `m4_ifval' and `m4_ifset' tests against the empty string. The
|
---|
| 289 | # difference is that `m4_ifset' is specialized on macros.
|
---|
| 290 | #
|
---|
| 291 | # In case of arguments of macros, eg. $1, it makes little difference.
|
---|
| 292 | # In the case of a macro `FOO', you don't want to check `m4_ifval(FOO,
|
---|
| 293 | # TRUE)', because if `FOO' expands with commas, there is a shifting of
|
---|
| 294 | # the arguments. So you want to run `m4_ifval([FOO])', but then you just
|
---|
| 295 | # compare the *string* `FOO' against `', which, of course fails.
|
---|
| 296 | #
|
---|
| 297 | # So you want the variation `m4_ifset' that expects a macro name as $1.
|
---|
| 298 | # If this macro is both defined and defined to a non empty value, then
|
---|
| 299 | # it runs TRUE, etc.
|
---|
| 300 |
|
---|
| 301 |
|
---|
| 302 | # m4_ifval(COND, [IF-TRUE], [IF-FALSE])
|
---|
| 303 | # -------------------------------------
|
---|
| 304 | # If COND is not the empty string, expand IF-TRUE, otherwise IF-FALSE.
|
---|
| 305 | # Comparable to m4_ifdef.
|
---|
| 306 | m4_define([m4_ifval],
|
---|
| 307 | [m4_if([$1], [], [$3], [$2])])
|
---|
| 308 |
|
---|
| 309 |
|
---|
| 310 | # m4_n(TEXT)
|
---|
| 311 | # ----------
|
---|
| 312 | # If TEXT is not empty, return TEXT and a new line, otherwise nothing.
|
---|
| 313 | m4_define([m4_n],
|
---|
| 314 | [m4_if([$1],
|
---|
| 315 | [], [],
|
---|
| 316 | [$1
|
---|
| 317 | ])])
|
---|
| 318 |
|
---|
| 319 |
|
---|
| 320 | # m4_ifvaln(COND, [IF-TRUE], [IF-FALSE])
|
---|
| 321 | # --------------------------------------
|
---|
| 322 | # Same as `m4_ifval', but add an extra newline to IF-TRUE or IF-FALSE
|
---|
| 323 | # unless that argument is empty.
|
---|
| 324 | m4_define([m4_ifvaln],
|
---|
| 325 | [m4_if([$1],
|
---|
| 326 | [], [m4_n([$3])],
|
---|
| 327 | [m4_n([$2])])])
|
---|
| 328 |
|
---|
| 329 |
|
---|
| 330 | # m4_ifset(MACRO, [IF-TRUE], [IF-FALSE])
|
---|
| 331 | # --------------------------------------
|
---|
| 332 | # If MACRO has no definition, or of its definition is the empty string,
|
---|
| 333 | # expand IF-FALSE, otherwise IF-TRUE.
|
---|
| 334 | m4_define([m4_ifset],
|
---|
| 335 | [m4_ifdef([$1],
|
---|
| 336 | [m4_ifval(_m4_defn([$1]), [$2], [$3])],
|
---|
| 337 | [$3])])
|
---|
| 338 |
|
---|
| 339 |
|
---|
| 340 | # m4_ifndef(NAME, [IF-NOT-DEFINED], [IF-DEFINED])
|
---|
| 341 | # -----------------------------------------------
|
---|
| 342 | m4_define([m4_ifndef],
|
---|
| 343 | [m4_ifdef([$1], [$3], [$2])])
|
---|
| 344 |
|
---|
| 345 |
|
---|
| 346 | # m4_case(SWITCH, VAL1, IF-VAL1, VAL2, IF-VAL2, ..., DEFAULT)
|
---|
| 347 | # -----------------------------------------------------------
|
---|
| 348 | # m4 equivalent of
|
---|
| 349 | # switch (SWITCH)
|
---|
| 350 | # {
|
---|
| 351 | # case VAL1:
|
---|
| 352 | # IF-VAL1;
|
---|
| 353 | # break;
|
---|
| 354 | # case VAL2:
|
---|
| 355 | # IF-VAL2;
|
---|
| 356 | # break;
|
---|
| 357 | # ...
|
---|
| 358 | # default:
|
---|
| 359 | # DEFAULT;
|
---|
| 360 | # break;
|
---|
| 361 | # }.
|
---|
| 362 | # All the values are optional, and the macro is robust to active
|
---|
| 363 | # symbols properly quoted.
|
---|
| 364 | #
|
---|
| 365 | # Please keep foreach.m4 in sync with any adjustments made here.
|
---|
| 366 | m4_define([m4_case],
|
---|
| 367 | [m4_if([$#], 0, [],
|
---|
| 368 | [$#], 1, [],
|
---|
| 369 | [$#], 2, [$2],
|
---|
| 370 | [$1], [$2], [$3],
|
---|
| 371 | [$0([$1], m4_shift3($@))])])
|
---|
| 372 |
|
---|
| 373 |
|
---|
| 374 | # m4_bmatch(SWITCH, RE1, VAL1, RE2, VAL2, ..., DEFAULT)
|
---|
| 375 | # -----------------------------------------------------
|
---|
| 376 | # m4 equivalent of
|
---|
| 377 | #
|
---|
| 378 | # if (SWITCH =~ RE1)
|
---|
| 379 | # VAL1;
|
---|
| 380 | # elif (SWITCH =~ RE2)
|
---|
| 381 | # VAL2;
|
---|
| 382 | # elif ...
|
---|
| 383 | # ...
|
---|
| 384 | # else
|
---|
| 385 | # DEFAULT
|
---|
| 386 | #
|
---|
| 387 | # All the values are optional, and the macro is robust to active symbols
|
---|
| 388 | # properly quoted.
|
---|
| 389 | #
|
---|
| 390 | # Please keep foreach.m4 in sync with any adjustments made here.
|
---|
| 391 | m4_define([m4_bmatch],
|
---|
| 392 | [m4_if([$#], 0, [m4_fatal([$0: too few arguments: $#])],
|
---|
| 393 | [$#], 1, [m4_fatal([$0: too few arguments: $#: $1])],
|
---|
| 394 | [$#], 2, [$2],
|
---|
| 395 | [m4_if(m4_bregexp([$1], [$2]), -1, [$0([$1], m4_shift3($@))],
|
---|
| 396 | [$3])])])
|
---|
| 397 |
|
---|
| 398 |
|
---|
| 399 | # m4_car(LIST)
|
---|
| 400 | # m4_cdr(LIST)
|
---|
| 401 | # ------------
|
---|
| 402 | # Manipulate m4 lists.
|
---|
| 403 | m4_define([m4_car], [[$1]])
|
---|
| 404 | m4_define([m4_cdr],
|
---|
| 405 | [m4_if([$#], 0, [m4_fatal([$0: cannot be called without arguments])],
|
---|
| 406 | [$#], 1, [],
|
---|
| 407 | [m4_dquote(m4_shift($@))])])
|
---|
| 408 |
|
---|
| 409 | # _m4_cdr(LIST)
|
---|
| 410 | # -------------
|
---|
| 411 | # Like m4_cdr, except include a leading comma unless only one element
|
---|
| 412 | # remains. Why? Because comparing a large list against [] is more
|
---|
| 413 | # expensive in expansion time than comparing the number of arguments; so
|
---|
| 414 | # _m4_cdr can be used to reduce the number of arguments when it is time
|
---|
| 415 | # to end recursion.
|
---|
| 416 | m4_define([_m4_cdr],
|
---|
| 417 | [m4_if([$#], 1, [],
|
---|
| 418 | [, m4_dquote(m4_shift($@))])])
|
---|
| 419 |
|
---|
| 420 |
|
---|
| 421 |
|
---|
| 422 | # m4_cond(TEST1, VAL1, IF-VAL1, TEST2, VAL2, IF-VAL2, ..., [DEFAULT])
|
---|
| 423 | # -------------------------------------------------------------------
|
---|
| 424 | # Similar to m4_if, except that each TEST is expanded when encountered.
|
---|
| 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 | ])
|
---|