# This file is part of Autoconf.
# Base M4 layer.
# Requires GNU M4.
-# Copyright (C) 1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
#
-# This program is free software; you can redistribute it and/or modify
+# Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
+# 2008 Free Software Foundation, Inc.
+#
+# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation; either version 2, or (at your option)
-# any later version.
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
-# along with this program; if not, write to the Free Software
-# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
-# 02110-1301, USA.
-#
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+
# As a special exception, the Free Software Foundation gives unlimited
# permission to copy, distribute and modify the configure scripts that
# are the output of Autoconf. You need not follow the terms of the GNU
# long macros we define.
ifdef([__gnu__], ,
[errprint(M4sugar requires GNU M4. Install it before installing M4sugar or
-set the M4 environment variable to its path name.)
+set the M4 environment variable to its absolute file name.)
m4exit(2)])
# Define DST as the definition of SRC.
# What's the difference between:
# 1. m4_copy([from], [to])
-# 2. m4_define([from], [to($@)])
-# Well, obviously 1 is more expansive in space. Maybe 2 is more expansive
+# 2. m4_define([to], [from($@)])
+# Well, obviously 1 is more expensive in space. Maybe 2 is more expensive
# in time, but because of the space cost of 1, it's not that obvious.
# Nevertheless, one huge difference is the handling of `$0'. If `from'
# uses `$0', then with 1, `to''s `$0' is `to', while it is `from' in 2.
-# The user will certainly prefer see `from'.
+# The user would certainly prefer to see `to'.
m4_define([m4_copy],
[m4_define([$2], m4_defn([$1]))])
# m4_rename(SRC, DST)
# -------------------
-# Rename the macro SRC as DST.
+# Rename the macro SRC to DST.
m4_define([m4_rename],
[m4_copy([$1], [$2])m4_undefine([$1])])
# m4_rename_m4(MACRO-NAME)
# ------------------------
-# Rename MACRO-NAME as m4_MACRO-NAME.
+# Rename MACRO-NAME to m4_MACRO-NAME.
m4_define([m4_rename_m4],
[m4_rename([$1], [m4_$1])])
# m4_copy_unm4(m4_MACRO-NAME)
# ---------------------------
-# Copy m4_MACRO-NAME as MACRO-NAME.
+# Copy m4_MACRO-NAME to MACRO-NAME.
m4_define([m4_copy_unm4],
[m4_copy([$1], m4_bpatsubst([$1], [^m4_\(.*\)], [[\1]]))])
m4_rename_m4([format])
m4_rename_m4([ifdef])
m4_rename([ifelse], [m4_if])
-m4_rename_m4([include])
+m4_undefine([include])
m4_rename_m4([incr])
m4_rename_m4([index])
m4_rename_m4([indir])
m4_rename_m4([pushdef])
m4_rename([regexp], [m4_bregexp])
m4_rename_m4([shift])
-m4_rename_m4([sinclude])
+m4_undefine([sinclude])
m4_rename_m4([substr])
m4_rename_m4([symbols])
m4_rename_m4([syscmd])
[m4_fatal([assert failed: $1], [$2])])])
+
## ------------- ##
## 3. Warnings. ##
## ------------- ##
-# m4_warning_ifelse(CATEGORY, IF-TRUE, IF-FALSE)
-# ----------------------------------------------
-# If the CATEGORY of warnings is enabled, expand IF_TRUE otherwise
-# IF-FALSE.
-#
-# The variable `m4_warnings' contains a comma separated list of
-# warnings which order is the converse from the one specified by
-# the user, i.e., if she specified `-W error,none,obsolete',
-# `m4_warnings' is `obsolete,none,error'. We read it from left to
-# right, and:
-# - if none or noCATEGORY is met, run IF-FALSE
-# - if all or CATEGORY is met, run IF-TRUE
-# - if there is nothing left, run IF-FALSE.
-m4_define([m4_warning_ifelse],
-[_m4_warning_ifelse([$1], [$2], [$3], m4_warnings)])
-
-
-# _m4_warning_ifelse(CATEGORY, IF-TRUE, IF-FALSE, WARNING1, ...)
-# --------------------------------------------------------------
-# Implementation of the loop described above.
-m4_define([_m4_warning_ifelse],
-[m4_case([$4],
- [$1], [$2],
- [all], [$2],
- [], [$3],
- [none], [$3],
- [no-$1], [$3],
- [$0([$1], [$2], [$3], m4_shiftn(4, $@))])])
-
-
-# _m4_warning_error_ifelse(IF-TRUE, IF-FALSE)
-# -------------------------------------------
-# The same as m4_warning_ifelse, but scan for `error' only.
-m4_define([_m4_warning_error_ifelse],
-[__m4_warning_error_ifelse([$1], [$2], m4_warnings)])
-
-
-# __m4_warning_error_ifelse(IF-TRUE, IF-FALSE)
-# --------------------------------------------
-# The same as _m4_warning_ifelse, but scan for `error' only.
-m4_define([__m4_warning_error_ifelse],
-[m4_case([$3],
- [error], [$1],
- [], [$2],
- [no-error], [$2],
- [$0([$1], [$2], m4_shiftn(3, $@))])])
-
-
-
-# _m4_warn(MESSAGE)
-# -----------------
-# Report MESSAGE as a warning, unless the user requested -W error,
-# in which case report a fatal error.
-m4_define([_m4_warn],
-[_m4_warning_error_ifelse([m4_fatal([$1])],
- [m4_warning([$1])])])
+# _m4_warn(CATEGORY, MESSAGE, STACK-TRACE)
+# ----------------------------------------
+# Report a MESSAGE to the user if the CATEGORY of warnings is enabled.
+# This is for traces only.
+# The STACK-TRACE is a \n-separated list of "LOCATION: MESSAGE".
+#
+# Within m4, the macro is a no-op. This macro really matters
+# when autom4te post-processes the trace output.
+m4_define([_m4_warn], [])
# m4_warn(CATEGORY, MESSAGE)
# --------------------------
-# Report a MESSAGE to the autoconf user if the CATEGORY of warnings
-# is requested (in fact, not disabled).
+# Report a MESSAGE to the user if the CATEGORY of warnings is enabled.
m4_define([m4_warn],
-[m4_warning_ifelse([$1], [_m4_warn([$2])])])
-
+[_m4_warn([$1], [$2],
+m4_ifdef([m4_expansion_stack],
+ [m4_defn([m4_expansion_stack])
+m4_location[: the top level]]))dnl
+])
# We also want to neutralize include (and sinclude for symmetry),
# but we want to extend them slightly: warn when a file is included
-# several times. This is in general a dangerous operation because
-# quite nobody quotes the first argument of m4_define.
+# several times. This is, in general, a dangerous operation, because
+# too many people forget to quote the first argument of m4_define.
#
# For instance in the following case:
# m4_define(foo, [bar])
# been included.
m4_define([m4_include_unique],
[m4_ifdef([m4_include($1)],
- [m4_warn([syntax], [file `$1' included several times])])dnl
+ [m4_warn([syntax], [file `$1' included several times])])dnl
m4_define([m4_include($1)])])
# m4_include(FILE)
# ----------------
-# As the builtin include, but warns against multiple inclusions.
+# Like the builtin include, but warns against multiple inclusions.
m4_define([m4_include],
[m4_include_unique([$1])dnl
m4_builtin([include], [$1])])
# m4_sinclude(FILE)
# -----------------
-# As the builtin sinclude, but warns against multiple inclusions.
+# Like the builtin sinclude, but warns against multiple inclusions.
m4_define([m4_sinclude],
[m4_include_unique([$1])dnl
m4_builtin([sinclude], [$1])])
# Both `m4_ifval' and `m4_ifset' tests against the empty string. The
# difference is that `m4_ifset' is specialized on macros.
#
-# In case of arguments of macros, eg $[1], it makes little difference.
+# In case of arguments of macros, eg. $1, it makes little difference.
# In the case of a macro `FOO', you don't want to check `m4_ifval(FOO,
# TRUE)', because if `FOO' expands with commas, there is a shifting of
# the arguments. So you want to run `m4_ifval([FOO])', but then you just
# compare the *string* `FOO' against `', which, of course fails.
#
-# So you want a variation of `m4_ifset' that expects a macro name as $[1].
+# So you want the variation `m4_ifset' that expects a macro name as $1.
# If this macro is both defined and defined to a non empty value, then
-# it runs TRUE etc.
+# it runs TRUE, etc.
# m4_ifval(COND, [IF-TRUE], [IF-FALSE])
m4_define([m4_n],
[m4_if([$1],
[], [],
- [$1
+ [$1
])])
m4_define([m4_ifvaln],
[m4_if([$1],
[], [m4_n([$3])],
- [m4_n([$2])])])
+ [m4_n([$2])])])
# m4_ifset(MACRO, [IF-TRUE], [IF-FALSE])
# expand IF-FALSE, otherwise IF-TRUE.
m4_define([m4_ifset],
[m4_ifdef([$1],
- [m4_if(m4_defn([$1]), [], [$3], [$2])],
- [$3])])
+ [m4_ifval(m4_defn([$1]), [$2], [$3])],
+ [$3])])
# m4_ifndef(NAME, [IF-NOT-DEFINED], [IF-DEFINED])
# All the values are optional, and the macro is robust to active symbols
# properly quoted.
m4_define([m4_bmatch],
-[m4_if([$#], 0, [],
- [$#], 1, [],
+[m4_if([$#], 0, [m4_fatal([$0: too few arguments: $#])],
+ [$#], 1, [m4_fatal([$0: too few arguments: $#: $1])],
[$#], 2, [$2],
[m4_if(m4_bregexp([$1], [$2]), -1, [$0([$1], m4_shiftn(3, $@))],
[$3])])])
+# m4_car(LIST)
+# m4_cdr(LIST)
+# ------------
+# Manipulate m4 lists.
+m4_define([m4_car], [[$1]])
+m4_define([m4_cdr],
+[m4_if([$#], 0, [m4_fatal([$0: cannot be called without arguments])],
+ [$#], 1, [],
+ [m4_dquote(m4_shift($@))])])
+
+
# m4_map(MACRO, LIST)
# -------------------
# Invoke MACRO($1), MACRO($2) etc. where $1, $2... are the elements
# of LIST (which can be lists themselves, for multiple arguments MACROs).
m4_define([m4_fst], [$1])
m4_define([m4_map],
-[m4_if([$2], [], [],
- [$2], [[]], [],
- [$1(m4_fst($2))[]dnl
-m4_map([$1], m4_cdr($2))])])
+[m4_if([$2], [[]], [],
+ [_m4_map([$1], [$2])])])
+m4_define([_m4_map],
+[m4_ifval([$2],
+ [$1(m4_fst($2))[]_m4_map([$1], m4_cdr($2))])])
# m4_map_sep(MACRO, SEPARATOR, LIST)
# arguments MACROs).
m4_define([m4_map_sep],
[m4_if([$3], [[]], [],
- [$1(m4_fst($3))[]dnl
-m4_if(m4_cdr($3),
- [[]], [],
- [$2])[]dnl
-m4_map_sep([$1], [$2], m4_cdr($3))])])
+ [$1(m4_fst($3))[]_m4_map([$2[]$1], m4_cdr($3))])])
## ---------------------------------------- ##
## 6. Enhanced version of some primitives. ##
## ---------------------------------------- ##
-# m4_patsubsts(STRING, RE1, SUBST1, RE2, SUBST2, ...)
-# ---------------------------------------------------
+# m4_bpatsubsts(STRING, RE1, SUBST1, RE2, SUBST2, ...)
+# ----------------------------------------------------
# m4 equivalent of
#
# $_ = STRING;
# All the values are optional, and the macro is robust to active symbols
# properly quoted.
#
-# I would have liked to name this macro `m4_patsubst', unfortunately,
+# I would have liked to name this macro `m4_bpatsubst', unfortunately,
# due to quotation problems, I need to double quote $1 below, therefore
# the anchors are broken :( I can't let users be trapped by that.
m4_define([m4_bpatsubsts],
[$#], 1, [m4_fatal([$0: too few arguments: $#: $1])],
[$#], 2, [m4_builtin([patsubst], $@)],
[$0(m4_builtin([patsubst], [[$1]], [$2], [$3]),
- m4_shiftn(3, $@))])])
+ m4_shiftn(3, $@))])])
# undefined.
m4_define([m4_defn],
[m4_ifndef([$1],
- [m4_fatal([$0: undefined macro: $1])])dnl
+ [m4_fatal([$0: undefined macro: $1])])dnl
m4_builtin([defn], $@)])
# ---------------------
m4_define([_m4_dumpdefs_up],
[m4_ifdef([$1],
- [m4_pushdef([_m4_dumpdefs], m4_defn([$1]))dnl
+ [m4_pushdef([_m4_dumpdefs], m4_defn([$1]))dnl
m4_dumpdef([$1])dnl
m4_popdef([$1])dnl
_m4_dumpdefs_up([$1])])])
# -----------------------
m4_define([_m4_dumpdefs_down],
[m4_ifdef([_m4_dumpdefs],
- [m4_pushdef([$1], m4_defn([_m4_dumpdefs]))dnl
+ [m4_pushdef([$1], m4_defn([_m4_dumpdefs]))dnl
m4_popdef([_m4_dumpdefs])dnl
_m4_dumpdefs_down([$1])])])
# undefined.
m4_define([m4_popdef],
[m4_ifndef([$1],
- [m4_fatal([$0: undefined macro: $1])])dnl
+ [m4_fatal([$0: undefined macro: $1])])dnl
m4_builtin([popdef], $@)])
# m4_noquote(STRING)
# ------------------
# Return the result of ignoring all quotes in STRING and invoking the
-# macros it contains. Amongst other things useful for enabling macro
-# invocations inside strings with [] blocks (for instance regexps and
-# help-strings).
+# macros it contains. Amongst other things, this is useful for enabling
+# macro invocations inside strings with [] blocks (for instance regexps
+# and help-strings). On the other hand, since all quotes are disabled,
+# any macro expanded during this time that relies on nested [] quoting
+# will likely crash and burn. This macro is seldom useful; consider
+# m4_unquote or m4_expand instead.
m4_define([m4_noquote],
[m4_changequote(-=<{,}>=-)$1-=<{}>=-m4_changequote([,])])
# undefined.
m4_define([m4_undefine],
[m4_ifndef([$1],
- [m4_fatal([$0: undefined macro: $1])])dnl
+ [m4_fatal([$0: undefined macro: $1])])dnl
m4_builtin([undefine], $@)])
## -------------------------- ##
-## 7. Implementing m4 loops. ##
+## 8. Implementing m4 loops. ##
## -------------------------- ##
# m4_for(VARIABLE, FIRST, LAST, [STEP = +/-1], EXPRESSION)
# --------------------------------------------------------
-# Expand EXPRESSION defining VARIABLE to FROM, FROM + 1, ..., TO.
+# Expand EXPRESSION defining VARIABLE to FROM, FROM + 1, ..., TO with
+# increments of STEP.
# Both limits are included, and bounds are checked for consistency.
m4_define([m4_for],
[m4_case(m4_sign(m4_eval($3 - $2)),
- 1, [m4_assert(m4_sign(m4_default($4, 1)) == 1)],
- -1, [m4_assert(m4_sign(m4_default($4, -1)) == -1)])dnl
+ 1, [m4_assert(m4_sign(m4_default($4, 1)) == 1)],
+ -1, [m4_assert(m4_sign(m4_default($4, -1)) == -1)])dnl
m4_pushdef([$1], [$2])dnl
m4_if(m4_eval([$3 > $2]), 1,
[_m4_for([$1], [$3], m4_default([$4], 1), [$5])],
# Implementing `foreach' loops in m4 is much more tricky than it may
-# seem. Actually, the example of a `foreach' loop in the m4
-# documentation is wrong: it does not quote the arguments properly,
-# which leads to undesirable expansions.
-#
-# The example in the documentation is:
+# seem. For example, the old M4 1.4.4 manual had an incorrect example,
+# which looked like this (when translated to m4sugar):
#
# | # foreach(VAR, (LIST), STMT)
# | m4_define([foreach],
-# | [m4_pushdef([$1])_foreach([$1], [$2], [$3])m4_popdef([$1])])
+# | [m4_pushdef([$1])_foreach([$1], [$2], [$3])m4_popdef([$1])])
# | m4_define([_arg1], [$1])
# | m4_define([_foreach],
-# | [m4_if([$2], [()], ,
-# | [m4_define([$1], _arg1$2)$3[]_foreach([$1],
-# | (shift$2),
-# | [$3])])])
+# | [m4_if([$2], [()], ,
+# | [m4_define([$1], _arg1$2)$3[]_foreach([$1], (m4_shift$2), [$3])])])
#
# But then if you run
#
# | m4_define([_arg1], [[$1]])
# | m4_define([_foreach],
# | [m4_if($2, [()], ,
-# | [m4_define([$1], [_arg1$2])$3[]_foreach([$1],
-# | [(shift$2)],
-# | [$3])])])
+# | [m4_define([$1], [_arg1$2])$3[]_foreach([$1], [(m4_shift$2)], [$3])])])
#
# which this time answers
#
# | m4_define([_arg1], [$1])
# | m4_define([_foreach],
# | [m4_if($2, [], ,
-# | [m4_define([$1], [_arg1($2)])$3[]_foreach([$1],
-# | [shift($2)],
-# | [$3])])])
+# | [m4_define([$1], [_arg1($2)])$3[]_foreach([$1], [m4_shift($2)], [$3])])])
#
#
# Now, just replace the `$2' with `m4_quote($2)' in the outer `m4_if'
-# to improve robustness, and you come up with a quite satisfactory
-# implementation.
+# to improve robustness, and you come up with a nice implementation
+# that doesn't require extra parentheses in the user's LIST.
+#
+# But wait - now the algorithm is quadratic, because every recursion of
+# the algorithm keeps the entire LIST and merely adds another m4_shift to
+# the quoted text. If the user has a lot of elements in LIST, you can
+# bring the system to its knees with the memory m4 then requires, or trip
+# the m4 --nesting-limit recursion factor. The only way to avoid
+# quadratic growth is ensure m4_shift is expanded prior to the recursion.
+# Hence the design below.
+#
+# The M4 manual now includes a chapter devoted to this issue, with
+# the lessons learned from m4sugar.
# m4_foreach(VARIABLE, LIST, EXPRESSION)
m4_define([m4_foreach],
[m4_pushdef([$1])_m4_foreach($@)m4_popdef([$1])])
-# Low level macros used to define m4_foreach.
-m4_define([m4_car], [[$1]])
-m4_define([m4_cdr], [m4_dquote(m4_shift($@))])
m4_define([_m4_foreach],
-[m4_if([$2], [[]], [],
- [m4_define([$1], m4_car($2))$3[]_m4_foreach([$1],
- m4_cdr($2),
- [$3])])])
+[m4_ifval([$2],
+ [m4_define([$1], m4_car($2))$3[]dnl
+_m4_foreach([$1], m4_cdr($2), [$3])])])
+
+
+# m4_foreach_w(VARIABLE, LIST, EXPRESSION)
+# ----------------------------------------
+#
+# Like m4_foreach, but the list is whitespace separated.
+#
+# This macro is robust to active symbols:
+# m4_foreach_w([Var], [ active
+# b act\
+# ive ], [-Var-])end
+# => -active--b--active-end
+#
+m4_define([m4_foreach_w],
+[m4_foreach([$1], m4_split(m4_normalize([$2])), [$3])])
## --------------------------- ##
-## 8. More diversion support. ##
+## 9. More diversion support. ##
## --------------------------- ##
# _m4_divert(DIVERSION-NAME or NUMBER)
# ------------------------------------
# If DIVERSION-NAME is the name of a diversion, return its number,
-# otherwise if is a NUMBER return it.
+# otherwise if it is a NUMBER return it.
m4_define([_m4_divert],
[m4_ifdef([_m4_divert($1)],
- [m4_indir([_m4_divert($1)])],
- [$1])])
+ [m4_indir([_m4_divert($1)])],
+ [$1])])
# KILL is only used to suppress output.
m4_define([_m4_divert(KILL)], -1)
+# _m4_divert_n_stack
+# ------------------
+# Print m4_divert_stack with newline prepended, if it's nonempty.
+m4_define([_m4_divert_n_stack],
+[m4_ifdef([m4_divert_stack], [
+m4_defn([m4_divert_stack])])])
+
+
# m4_divert(DIVERSION-NAME)
# -------------------------
# Change the diversion stream to DIVERSION-NAME.
m4_define([m4_divert],
-[m4_define([m4_divert_stack],
- m4_location[: $0: $1]m4_ifdef([m4_divert_stack], [
-m4_defn([m4_divert_stack])]))dnl
+[m4_define([m4_divert_stack], m4_location[: $0: $1]_m4_divert_n_stack)dnl
m4_builtin([divert], _m4_divert([$1]))dnl
])
# ------------------------------
# Change the diversion stream to DIVERSION-NAME, while stacking old values.
m4_define([m4_divert_push],
-[m4_pushdef([m4_divert_stack],
- m4_location[: $0: $1]m4_ifdef([m4_divert_stack], [
-m4_defn([m4_divert_stack])]))dnl
+[m4_pushdef([m4_divert_stack], m4_location[: $0: $1]_m4_divert_n_stack)dnl
m4_pushdef([_m4_divert_diversion], [$1])dnl
-m4_builtin([divert], _m4_divert(_m4_divert_diversion))dnl
+m4_builtin([divert], _m4_divert([$1]))dnl
])
# -------------------------------
# Change the diversion stream to its previous value, unstacking it.
# If specified, verify we left DIVERSION-NAME.
+# When we pop the last value from the stack, we divert to -1.
m4_define([m4_divert_pop],
-[m4_ifval([$1],
- [m4_if(_m4_divert([$1]), m4_divnum, [],
- [m4_fatal([$0($1): diversion mismatch: ]
-m4_defn([m4_divert_stack]))])])dnl
+[m4_ifndef([_m4_divert_diversion],
+ [m4_fatal([too many m4_divert_pop])])dnl
+m4_if([$1], [], [],
+ [$1], m4_defn([_m4_divert_diversion]), [],
+ [m4_fatal([$0($1): diversion mismatch: ]_m4_divert_n_stack)])dnl
+m4_popdef([m4_divert_stack])dnl
m4_popdef([_m4_divert_diversion])dnl
-dnl m4_ifndef([_m4_divert_diversion],
-dnl [m4_fatal([too many m4_divert_pop])])dnl
m4_builtin([divert],
- m4_ifdef([_m4_divert_diversion],
- [_m4_divert(_m4_divert_diversion)], -1))dnl
-m4_popdef([m4_divert_stack])dnl
+ m4_ifdef([_m4_divert_diversion],
+ [_m4_divert(m4_defn([_m4_divert_diversion]))],
+ -1))dnl
])
# m4_divert_once(DIVERSION-NAME, CONTENT)
# ---------------------------------------
-# Output once CONTENT into DIVERSION-NAME (which may be a number
-# actually). An end of line is appended for free to CONTENT.
+# Output CONTENT into DIVERSION-NAME once, if not already there.
+# An end of line is appended for free to CONTENT.
m4_define([m4_divert_once],
[m4_expand_once([m4_divert_text([$1], [$2])])])
# m4_undivert(DIVERSION-NAME)
# ---------------------------
-# Undivert DIVERSION-NAME.
+# Undivert DIVERSION-NAME. Unlike the M4 version, this only takes a single
+# diversion identifier, and should not be used to undivert files.
m4_define([m4_undivert],
[m4_builtin([undivert], _m4_divert([$1]))])
-## -------------------------------------------- ##
-## 8. Defining macros with bells and whistles. ##
-## -------------------------------------------- ##
+## --------------------------------------------- ##
+## 10. Defining macros with bells and whistles. ##
+## --------------------------------------------- ##
# `m4_defun' is basically `m4_define' but it equips the macro with the
# needed machinery for `m4_require'. A macro must be m4_defun'd if
# the previous macros (by Axel Thimm).
#
#
-# The first idea: why using diversions?
-# -------------------------------------
+# The first idea: why use diversions?
+# -----------------------------------
#
# When a macro requires another, the other macro is expanded in new
# diversion, GROW. When the outer macro is fully expanded, we first
# | m4_defun([TEST3], [Test...3])
#
# Because m4_require is not required to be first in the outer macros, we
-# must keep the expansions of the various level of m4_require separated.
+# must keep the expansions of the various levels of m4_require separated.
# Right before executing the epilogue of TEST1, we have:
#
-# GROW - 2: Test...3
-# GROW - 1: Test...2
-# GROW: Test...1
-# BODY:
+# GROW - 2: Test...3
+# GROW - 1: Test...2
+# GROW: Test...1
+# BODY:
#
# Finally the epilogue of TEST1 undiverts GROW - 2, GROW - 1, and
# GROW into the regular flow, BODY.
#
-# GROW - 2:
-# GROW - 1:
-# GROW:
-# BODY: Test...3; Test...2; Test...1
+# GROW - 2:
+# GROW - 1:
+# GROW:
+# BODY: Test...3; Test...2; Test...1
#
# (The semicolons are here for clarification, but of course are not
# emitted.) This is what Autoconf 2.0 (I think) to 2.13 (I'm sure)
#
# The dependencies between the macros are:
#
-# 3 --- 2b
-# / \ is m4_require'd by
-# / \ left -------------------- right
-# 2a ------------ 1
+# 3 --- 2b
+# / \ is m4_require'd by
+# / \ left -------------------- right
+# 2a ------------ 1
#
# If you strictly apply the rules given in the previous section you get:
#
-# GROW - 2: TEST3
-# GROW - 1: TEST2a; TEST2b
-# GROW: TEST1
-# BODY:
+# GROW - 2: TEST3
+# GROW - 1: TEST2a; TEST2b
+# GROW: TEST1
+# BODY:
#
# (TEST2a, although required by TEST3 is not expanded in GROW - 3
# because is has already been expanded before in GROW - 1, so it has
# been AC_PROVIDE'd, so it is not expanded again) so when you undivert
# the stack of diversions, you get:
#
-# GROW - 2:
-# GROW - 1:
-# GROW:
-# BODY: TEST3; TEST2a; TEST2b; TEST1
+# GROW - 2:
+# GROW - 1:
+# GROW:
+# BODY: TEST3; TEST2a; TEST2b; TEST1
#
# i.e., TEST2a is expanded after TEST3 although the latter required the
# former.
#
-# Starting from 2.50, uses an implementation provided by Axel Thimm.
+# Starting from 2.50, we use an implementation provided by Axel Thimm.
# The idea is simple: the order in which macros are emitted must be the
-# same as the one in which macro are expanded. (The bug above can
-# indeed be described as: a macro has been AC_PROVIDE'd, but it is
-# emitted after: the lack of correlation between emission and expansion
-# order is guilty).
+# same as the one in which macros are expanded. (The bug above can
+# indeed be described as: a macro has been AC_PROVIDE'd before its
+# dependent, but it is emitted after: the lack of correlation between
+# emission and expansion order is guilty).
#
-# How to do that? You keeping the stack of diversions to elaborate the
+# How to do that? You keep the stack of diversions to elaborate the
# macros, but each time a macro is fully expanded, emit it immediately.
#
# In the example above, when TEST2a is expanded, but it's epilogue is
# not run yet, you have:
#
-# GROW - 2:
-# GROW - 1: TEST2a
-# GROW: Elaboration of TEST1
-# BODY:
+# GROW - 2:
+# GROW - 1: TEST2a
+# GROW: Elaboration of TEST1
+# BODY:
#
# The epilogue of TEST2a emits it immediately:
#
-# GROW - 2:
-# GROW - 1:
-# GROW: Elaboration of TEST1
-# BODY: TEST2a
+# GROW - 2:
+# GROW - 1:
+# GROW: Elaboration of TEST1
+# BODY: TEST2a
#
# TEST2b then requires TEST3, so right before the epilogue of TEST3, you
# have:
#
-# GROW - 2: TEST3
-# GROW - 1: Elaboration of TEST2b
-# GROW: Elaboration of TEST1
-# BODY: TEST2a
+# GROW - 2: TEST3
+# GROW - 1: Elaboration of TEST2b
+# GROW: Elaboration of TEST1
+# BODY: TEST2a
#
# The epilogue of TEST3 emits it:
#
-# GROW - 2:
-# GROW - 1: Elaboration of TEST2b
-# GROW: Elaboration of TEST1
-# BODY: TEST2a; TEST3
+# GROW - 2:
+# GROW - 1: Elaboration of TEST2b
+# GROW: Elaboration of TEST1
+# BODY: TEST2a; TEST3
#
# TEST2b is now completely expanded, and emitted:
#
-# GROW - 2:
-# GROW - 1:
-# GROW: Elaboration of TEST1
-# BODY: TEST2a; TEST3; TEST2b
+# GROW - 2:
+# GROW - 1:
+# GROW: Elaboration of TEST1
+# BODY: TEST2a; TEST3; TEST2b
#
# and finally, TEST1 is finished and emitted:
#
-# GROW - 2:
-# GROW - 1:
-# GROW:
-# BODY: TEST2a; TEST3; TEST2b: TEST1
+# GROW - 2:
+# GROW - 1:
+# GROW:
+# BODY: TEST2a; TEST3; TEST2b: TEST1
#
-# The idea, is simple, but the implementation is a bit evolved. If you
+# The idea is simple, but the implementation is a bit evolved. If you
# are like me, you will want to see the actual functioning of this
# implementation to be convinced. The next section gives the full
# details.
#
# We consider the macros above, and this configure.ac:
#
-# AC_INIT
-# TEST1
+# AC_INIT
+# TEST1
#
# You should keep the definitions of _m4_defun_pro, _m4_defun_epi, and
# m4_require at hand to follow the steps.
#
-# This implements tries not to assume that of the current diversion is
+# This implements tries not to assume that the current diversion is
# BODY, so as soon as a macro (m4_defun'd) is expanded, we first
# record the current diversion under the name _m4_divert_dump (denoted
# DUMP below for short). This introduces an important difference with
# the previous versions of Autoconf: you cannot use m4_require if you
-# were not inside an m4_defun'd macro, and especially, you cannot
+# are not inside an m4_defun'd macro, and especially, you cannot
# m4_require directly from the top level.
#
# We have not tried to simulate the old behavior (better yet, we
# diversion stack: BODY |-
#
# * TEST1 is expanded
-# The prologue of TEST1 sets AC_DIVERSION_DUMP, which is the diversion
+# The prologue of TEST1 sets _m4_divert_dump, which is the diversion
# where the current elaboration will be dumped, to the current
# diversion. It also m4_divert_push to GROW, where the full
# expansion of TEST1 and its dependencies will be elaborated.
-# DUMP: BODY
-# BODY: empty
-# diversions: GROW, BODY |-
-#
-# * TEST1 requires TEST2a: prologue
-# m4_require m4_divert_pushes another temporary diversion GROW - 1 (in
-# fact, the diversion whose number is one less than the current
-# diversion), and expands TEST2a in there.
-# DUMP: BODY
-# BODY: empty
-# diversions: GROW-1, GROW, BODY |-
-#
-# * TEST2a is expanded.
-# Its prologue pushes the current diversion again.
-# DUMP: BODY
-# BODY: empty
-# diversions: GROW - 1, GROW - 1, GROW, BODY |-
-# It is expanded in GROW - 1, and GROW - 1 is popped by the epilogue
-# of TEST2a.
# DUMP: BODY
-# BODY: nothing
+# BODY: empty
+# diversions: GROW, BODY |-
+#
+# * TEST1 requires TEST2a
+# _m4_require_call m4_divert_pushes another temporary diversion,
+# GROW - 1, and expands TEST2a in there.
+# DUMP: BODY
+# BODY: empty
# GROW - 1: TEST2a
# diversions: GROW - 1, GROW, BODY |-
+# Than the content of the temporary diversion is moved to DUMP and the
+# temporary diversion is popped.
+# DUMP: BODY
+# BODY: TEST2a
+# diversions: GROW, BODY |-
+#
+# * TEST1 requires TEST2b
+# Again, _m4_require_call pushes GROW - 1 and heads to expand TEST2b.
+# DUMP: BODY
+# BODY: TEST2a
+# diversions: GROW - 1, GROW, BODY |-
#
-# * TEST1 requires TEST2a: epilogue
-# The content of the current diversion is appended to DUMP (and removed
-# from the current diversion). A diversion is popped.
-# DUMP: BODY
-# BODY: TEST2a
-# diversions: GROW, BODY |-
-#
-# * TEST1 requires TEST2b: prologue
-# m4_require pushes GROW - 1 and expands TEST2b.
-# DUMP: BODY
-# BODY: TEST2a
-# diversions: GROW - 1, GROW, BODY |-
-#
-# * TEST2b is expanded.
-# Its prologue pushes the current diversion again.
-# DUMP: BODY
-# BODY: TEST2a
-# diversions: GROW - 1, GROW - 1, GROW, BODY |-
-# The body is expanded here.
-#
-# * TEST2b requires TEST3: prologue
-# m4_require pushes GROW - 2 and expands TEST3.
-# DUMP: BODY
-# BODY: TEST2a
-# diversions: GROW - 2, GROW - 1, GROW - 1, GROW, BODY |-
-#
-# * TEST3 is expanded.
-# Its prologue pushes the current diversion again.
-# DUMP: BODY
-# BODY: TEST2a
-# diversions: GROW-2, GROW-2, GROW-1, GROW-1, GROW, BODY |-
-# TEST3 requires TEST2a, but TEST2a has already been AC_PROVIDE'd, so
-# nothing happens. It's body is expanded here, and its epilogue pops a
-# diversion.
-# DUMP: BODY
-# BODY: TEST2a
-# GROW - 2: TEST3
-# diversions: GROW - 2, GROW - 1, GROW - 1, GROW, BODY |-
-#
-# * TEST2b requires TEST3: epilogue
-# The current diversion is appended to DUMP, and a diversion is popped.
-# DUMP: BODY
-# BODY: TEST2a; TEST3
-# diversions: GROW - 1, GROW - 1, GROW, BODY |-
-# The content of TEST2b is expanded here.
-# DUMP: BODY
-# BODY: TEST2a; TEST3
-# GROW - 1: TEST2b,
-# diversions: GROW - 1, GROW - 1, GROW, BODY |-
-# The epilogue of TEST2b pops a diversion.
-# DUMP: BODY
-# BODY: TEST2a; TEST3
-# GROW - 1: TEST2b,
-# diversions: GROW - 1, GROW, BODY |-
-#
-# * TEST1 requires TEST2b: epilogue
-# The current diversion is appended to DUMP, and a diversion is popped.
-# DUMP: BODY
-# BODY: TEST2a; TEST3; TEST2b
-# diversions: GROW, BODY |-
+# * TEST2b requires TEST3
+# _m4_require_call pushes GROW - 2 and expands TEST3 here.
+# (TEST3 requires TEST2a, but TEST2a has already been m4_provide'd, so
+# nothing happens.)
+# DUMP: BODY
+# BODY: TEST2a
+# GROW - 2: TEST3
+# diversions: GROW - 2, GROW - 1, GROW, BODY |-
+# Than the diversion is appended to DUMP, and popped.
+# DUMP: BODY
+# BODY: TEST2a; TEST3
+# diversions: GROW - 1, GROW, BODY |-
+#
+# * TEST1 requires TEST2b (contd.)
+# The content of TEST2b is expanded...
+# DUMP: BODY
+# BODY: TEST2a; TEST3
+# GROW - 1: TEST2b,
+# diversions: GROW - 1, GROW, BODY |-
+# ... and moved to DUMP.
+# DUMP: BODY
+# BODY: TEST2a; TEST3; TEST2b
+# diversions: GROW, BODY |-
#
# * TEST1 is expanded: epilogue
-# TEST1's own content is in GROW, and it's epilogue pops a diversion.
-# DUMP: BODY
-# BODY: TEST2a; TEST3; TEST2b
-# GROW: TEST1
-# diversions: BODY |-
-# Here, the epilogue of TEST1 notices the elaboration is done because
-# DUMP and the current diversion are the same, it then undiverts
-# GROW by hand, and undefines DUMP.
+# TEST1's own content is in GROW...
+# DUMP: BODY
+# BODY: TEST2a; TEST3; TEST2b
+# GROW: TEST1
+# diversions: BODY |-
+# ... and it's epilogue moves it to DUMP and then undefines DUMP.
# DUMP: undefined
# BODY: TEST2a; TEST3; TEST2b; TEST1
# diversions: BODY |-
# we prepend its name in m4_expansion_stack, and when we exit the
# macro, we remove it (thanks to pushdef/popdef).
#
-# In addition, we want to use the expansion stack to detect circular
-# m4_require dependencies. This means we need to browse the stack to
-# check whether a macro being expanded is m4_require'd. For ease of
-# implementation, and certainly for the benefit of performances, we
-# don't browse the m4_expansion_stack, rather each time we expand a
-# macro FOO we define _m4_expanding(FOO). Then m4_require(BAR) simply
-# needs to check whether _m4_expanding(BAR) is defined to diagnose a
-# circular dependency.
-#
-# To improve the diagnostic, in addition to keeping track of the stack
-# of macro calls, m4_expansion_stack also records the m4_require
-# stack. Note that therefore an m4_defun'd macro being required will
-# appear twice in the stack: the first time because it is required,
-# the second because it is expanded. We can avoid this, but it has
-# two small drawbacks: (i) the implementation is slightly more
-# complex, and (ii) it hides the difference between define'd macros
-# (which don't appear in m4_expansion_stack) and m4_defun'd macros
-# (which do). The more debugging information, the better.
+# In addition, we want to detect circular m4_require dependencies.
+# Each time we expand a macro FOO we define _m4_expanding(FOO); and
+# m4_require(BAR) simply checks whether _m4_expanding(BAR) is defined.
# m4_expansion_stack_push(TEXT)
# -----------------------------
m4_define([m4_expansion_stack_push],
[m4_pushdef([m4_expansion_stack],
- [$1]m4_ifdef([m4_expansion_stack], [
+ [$1]m4_ifdef([m4_expansion_stack], [
m4_defn([m4_expansion_stack])]))])
# m4_expansion_stack_pop
# ----------------------
-# Dump the expansion stack.
m4_define([m4_expansion_stack_pop],
[m4_popdef([m4_expansion_stack])])
# Dump the expansion stack.
m4_define([m4_expansion_stack_dump],
[m4_ifdef([m4_expansion_stack],
- [m4_errprintn(m4_defn([m4_expansion_stack]))])dnl
+ [m4_errprintn(m4_defn([m4_expansion_stack]))])dnl
m4_errprintn(m4_location[: the top level])])
# -------------------------
# The prologue for Autoconf macros.
m4_define([_m4_defun_pro],
-[m4_expansion_stack_push(m4_defn([m4_location($1)])[: $1 is expanded from...])dnl
+[m4_ifndef([m4_expansion_stack], [_m4_defun_pro_outer[]])dnl
+m4_expansion_stack_push(m4_defn([m4_location($1)])[: $1 is expanded from...])dnl
m4_pushdef([_m4_expanding($1)])dnl
-m4_ifdef([_m4_divert_dump],
- [m4_divert_push(m4_defn([_m4_divert_diversion]))],
- [m4_copy([_m4_divert_diversion], [_m4_divert_dump])dnl
-m4_divert_push([GROW])])dnl
])
+m4_define([_m4_defun_pro_outer],
+[m4_copy([_m4_divert_diversion], [_m4_divert_dump])dnl
+m4_divert_push([GROW])dnl
+])
# _m4_defun_epi(MACRO-NAME)
# -------------------------
# The Epilogue for Autoconf macros. MACRO-NAME only helps tracing
# the PRO/EPI pairs.
m4_define([_m4_defun_epi],
-[m4_divert_pop()dnl
-m4_if(_m4_divert_dump, _m4_divert_diversion,
- [m4_undivert([GROW])dnl
-m4_undefine([_m4_divert_dump])])dnl
+[m4_popdef([_m4_expanding($1)])dnl
m4_expansion_stack_pop()dnl
-m4_popdef([_m4_expanding($1)])dnl
+m4_ifndef([m4_expansion_stack], [_m4_defun_epi_outer[]])dnl
m4_provide([$1])dnl
])
+m4_define([_m4_defun_epi_outer],
+[m4_undefine([_m4_divert_dump])dnl
+m4_divert_pop([GROW])dnl
+m4_undivert([GROW])dnl
+])
+
# m4_defun(NAME, EXPANSION)
# -------------------------
m4_define([m4_defun],
[m4_define([m4_location($1)], m4_location)dnl
m4_define([$1],
- [_m4_defun_pro([$1])$2[]_m4_defun_epi([$1])])])
+ [_m4_defun_pro([$1])$2[]_m4_defun_epi([$1])])])
# m4_defun_once(NAME, EXPANSION)
m4_define([m4_defun_once],
[m4_define([m4_location($1)], m4_location)dnl
m4_define([$1],
- [m4_provide_if([$1],
- [m4_warn([syntax], [$1 invoked multiple times])],
- [_m4_defun_pro([$1])$2[]_m4_defun_epi([$1])])])])
+ [m4_provide_if([$1],
+ [m4_warn([syntax], [$1 invoked multiple times])],
+ [_m4_defun_pro([$1])$2[]_m4_defun_epi([$1])])])])
# m4_pattern_forbid(ERE, [WHY])
# -----------------------------
-# Declare that no token matching the extended regular expression ERE
-# should be seen in the output but if...
+# Declare that no token matching the forbidden extended regular
+# expression ERE should be seen in the output unless...
m4_define([m4_pattern_forbid], [])
# m4_pattern_allow(ERE)
# ---------------------
-# ... but if that token matches the extended regular expression ERE.
+# ... that token also matches the allowed extended regular expression ERE.
# Both used via traces.
m4_define([m4_pattern_allow], [])
-## ----------------------------- ##
-## Dependencies between macros. ##
-## ----------------------------- ##
+## --------------------------------- ##
+## 11. Dependencies between macros. ##
+## --------------------------------- ##
# m4_before(THIS-MACRO-NAME, CALLED-MACRO-NAME)
# ---------------------------------------------
+# Issue a warning if CALLED-MACRO-NAME was called before THIS-MACRO-NAME.
m4_define([m4_before],
[m4_provide_if([$2],
- [m4_warn([syntax], [$2 was called before $1])])])
+ [m4_warn([syntax], [$2 was called before $1])])])
# m4_require(NAME-TO-CHECK, [BODY-TO-EXPAND = NAME-TO-CHECK])
# `extension' prevents `AC_LANG_COMPILER' from having actual arguments that
# it passes to `AC_LANG_COMPILER(C)'.
m4_define([m4_require],
-[m4_expansion_stack_push(m4_location[: $1 is required by...])dnl
-m4_ifdef([_m4_expanding($1)],
- [m4_fatal([$0: circular dependency of $1])])dnl
+[m4_ifdef([_m4_expanding($1)],
+ [m4_fatal([$0: circular dependency of $1])])dnl
m4_ifndef([_m4_divert_dump],
- [m4_fatal([$0: cannot be used outside of an m4_defun'd macro])])dnl
+ [m4_fatal([$0($1): cannot be used outside of an m4_defun'd macro])])dnl
m4_provide_if([$1],
- [],
- [m4_divert_push(m4_eval(m4_divnum - 1))dnl
+ [],
+ [_m4_require_call([$1], [$2])])dnl
+])
+
+
+# _m4_require_call(BODY-TO-EXPAND)
+# --------------------------------
+# If m4_require decides to expand the body, it calls this macro.
+m4_define([_m4_require_call],
+[m4_define([_m4_divert_grow], m4_decr(_m4_divert_grow))dnl
+m4_divert_push(_m4_divert_grow)dnl
m4_default([$2], [$1])
-m4_divert(m4_defn([_m4_divert_dump]))dnl
-m4_undivert(m4_defn([_m4_divert_diversion]))dnl
-m4_divert_pop(m4_defn([_m4_divert_dump]))])dnl
m4_provide_if([$1],
- [],
- [m4_warn([syntax],
- [$1 is m4_require'd but is not m4_defun'd])])dnl
-m4_expansion_stack_pop()dnl
+ [],
+ [m4_warn([syntax],
+ [$1 is m4_require'd but not m4_defun'd])])dnl
+m4_divert(m4_defn([_m4_divert_dump]))dnl
+m4_undivert(_m4_divert_grow)dnl
+m4_divert_pop(_m4_divert_grow)dnl
+m4_define([_m4_divert_grow], m4_incr(_m4_divert_grow))dnl
])
+# _m4_divert_grow
+# ---------------
+# The counter for _m4_require_call.
+m4_define([_m4_divert_grow], _m4_divert([GROW]))
+
+
# m4_expand_once(TEXT, [WITNESS = TEXT])
# --------------------------------------
# If TEXT has never been expanded, expand it *here*. Use WITNESS as
# as a memory that TEXT has already been expanded.
m4_define([m4_expand_once],
[m4_provide_if(m4_ifval([$2], [[$2]], [[$1]]),
- [],
- [m4_provide(m4_ifval([$2], [[$2]], [[$1]]))[]$1])])
+ [],
+ [m4_provide(m4_ifval([$2], [[$2]], [[$1]]))[]$1])])
# m4_provide(MACRO-NAME)
# information is coded.
m4_define([m4_provide_if],
[m4_ifdef([m4_provide($1)],
- [$2], [$3])])
+ [$2], [$3])])
-## -------------------- ##
-## 9. Text processing. ##
-## -------------------- ##
+## --------------------- ##
+## 12. Text processing. ##
+## --------------------- ##
# m4_cr_letters
# m4_re_escape(STRING)
# --------------------
-# Escape BRE active characters in STRING.
+# Escape RE active characters in STRING.
m4_define([m4_re_escape],
[m4_bpatsubst([$1],
- [[][+*.]], [\\\&])])
+ [[][*+.?\^$]], [\\\&])])
# m4_re_string
# ------------
# Regexp for `[a-zA-Z_0-9]*'
+# m4_dquote provides literal [] for the character class.
m4_define([m4_re_string],
-m4_defn([m4_cr_symbols2])dnl
+m4_dquote(m4_defn([m4_cr_symbols2]))dnl
[*]dnl
)
# ----------
# Regexp for `[a-zA-Z_][a-zA-Z_0-9]*'
m4_define([m4_re_word],
-m4_defn([m4_cr_symbols1])dnl
+m4_dquote(m4_defn([m4_cr_symbols1]))dnl
m4_defn([m4_re_string])dnl
)
#
# REGEXP specifies where to split. Default is [\t ]+.
#
-# Pay attention to the m4_changequotes. Inner m4_changequotes exist for
-# obvious reasons (we want to insert square brackets). Outer
-# m4_changequotes are needed because otherwise the m4 parser, when it
-# sees the closing bracket we add to the result, believes it is the
-# end of the body of the macro we define.
+# If STRING is empty, the result is an empty list.
+#
+# Pay attention to the m4_changequotes. When m4 reads the definition of
+# m4_split, it still has quotes set to [ and ]. Luckily, these are matched
+# in the macro body, so the definition is stored correctly.
#
# Also, notice that $1 is quoted twice, since we want the result to
# be quoted. Then you should understand that the argument of
# m4_split([active active ])end
# => [active], [active], []end
-m4_changequote(<<, >>)
-m4_define(<<m4_split>>,
-<<m4_changequote(``, '')dnl
+m4_define([m4_split],
+[m4_ifval([$1], [_m4_split($@)])])
+
+m4_define([_m4_split],
+[m4_changequote(``, '')dnl
[dnl Can't use m4_default here instead of m4_if, because m4_default uses
dnl [ and ] as quotes.
m4_bpatsubst(````$1'''',
- m4_if(``$2'',, ``[ ]+'', ``$2''),
+ m4_if(``$2'',, ``[ ]+'', ``$2''),
``], ['')]dnl
-m4_changequote([, ])>>)
-m4_changequote([, ])
+m4_changequote([, ])])
#
# This macro is robust to active symbols.
# m4_define(active, ACTIVE)
-# m4_strip([ active active ])end
+# m4_strip([ active <tab> <tab>active ])end
# => active activeend
#
-# This macro is fun! Because we want to preserve active symbols, STRING
-# must be quoted for each evaluation, which explains there are 4 levels
-# of brackets around $1 (don't forget that the result must be quoted
-# too, hence one more quoting than applications).
+# Because we want to preserve active symbols, STRING must be double-quoted.
#
# Then notice the 2 last patterns: they are in charge of removing the
# leading/trailing spaces. Why not just `[^ ]'? Because they are
# character, since there are two leading `['; equally for the last pattern.
m4_define([m4_strip],
[m4_bpatsubsts([[$1]],
- [[ ]+], [ ],
- [^\(..\) ], [\1],
- [ \(..\)$], [\1])])
+ [[ ]+], [ ],
+ [^\(..\) ], [\1],
+ [ \(..\)$], [\1])])
# m4_normalize(STRING)
# Produce ARG1SEPARG2...SEPARGn.
m4_defun([m4_join],
[m4_case([$#],
- [1], [],
- [2], [[$2]],
- [[$2][$1]$0([$1], m4_shiftn(2, $@))])])
+ [1], [],
+ [2], [[$2]],
+ [[$2][$1]$0([$1], m4_shiftn(2, $@))])])
# => active
m4_define([m4_append],
[m4_define([$1],
- m4_ifdef([$1], [m4_defn([$1])$3])[$2])])
+ m4_ifdef([$1], [m4_defn([$1])$3])[$2])])
+# m4_prepend(MACRO-NAME, STRING, [SEPARATOR])
+# -------------------------------------------
+# Same, but prepend.
+m4_define([m4_prepend],
+[m4_define([$1],
+ [$2]m4_ifdef([$1], [$3[]m4_defn([$1])]))])
# m4_append_uniq(MACRO-NAME, STRING, [SEPARATOR])
# -----------------------------------------------
# As `m4_append', but append only if not yet present.
m4_define([m4_append_uniq],
[m4_ifdef([$1],
- [m4_bmatch([$3]m4_defn([$1])[$3], m4_re_escape([$3$2$3]), [],
- [m4_append($@)])],
- [m4_append($@)])])
+ [m4_bmatch([$3]m4_defn([$1])[$3], m4_re_escape([$3$2$3]), [],
+ [m4_append($@)])],
+ [m4_append($@)])])
# m4_text_wrap(STRING, [PREFIX], [FIRST-PREFIX], [WIDTH])
# -------------------------------------------------------
# Expands into STRING wrapped to hold in WIDTH columns (default = 79).
-# If prefix is set, each line is prefixed with it. If FIRST-PREFIX is
-# specified, then the first line is prefixed with it. As a special
-# case, if the length of the first prefix is greater than that of
-# PREFIX, then FIRST-PREFIX will be left alone on the first line.
+# If PREFIX is given, each line is prefixed with it. If FIRST-PREFIX is
+# specified, then the first line is prefixed with it. As a special case,
+# if the length of FIRST-PREFIX is greater than that of PREFIX, then
+# FIRST-PREFIX will be left alone on the first line.
#
# Typical outputs are:
#
#
# m4_text_wrap([Super long documentation.], [ ], [ --too-wide ], 30)
# => --too-wide
-# => Super long
-# => documentation.
+# => Super long
+# => documentation.
#
# FIXME: there is no checking of a longer PREFIX than WIDTH, but do
# we really want to bother with people trying each single corner
# of a software?
#
+# more important:
+# FIXME: handle quadrigraphs correctly, both in TEXT and in FIRST_PREFIX.
+#
# This macro does not leave a trailing space behind the last word,
# what complicates it a bit. The algorithm is stupid simple: all the
# words are preceded by m4_Separator which is defined to empty for the
# first word, and then ` ' (single space) for all the others.
m4_define([m4_text_wrap],
-[m4_pushdef([m4_Prefix], m4_default([$2], []))dnl
+[m4_pushdef([m4_Prefix], [$2])dnl
m4_pushdef([m4_Prefix1], m4_default([$3], [m4_Prefix]))dnl
m4_pushdef([m4_Width], m4_default([$4], 79))dnl
m4_pushdef([m4_Cursor], m4_len(m4_Prefix1))dnl
m4_if(m4_eval(m4_Cursor > m4_len(m4_Prefix)),
1, [m4_define([m4_Cursor], m4_len(m4_Prefix))
m4_Prefix])[]dnl
-m4_foreach([m4_Word], m4_quote(m4_split(m4_normalize([$1]))),
+m4_foreach_w([m4_Word], [$1],
[m4_define([m4_Cursor], m4_eval(m4_Cursor + m4_len(m4_defn([m4_Word])) + 1))dnl
dnl New line if too long, else insert a space unless it is the first
dnl of the words.
m4_if(m4_eval(m4_Cursor > m4_Width),
1, [m4_define([m4_Cursor],
- m4_eval(m4_len(m4_Prefix) + m4_len(m4_defn([m4_Word])) + 1))]
+ m4_eval(m4_len(m4_Prefix) + m4_len(m4_defn([m4_Word])) + 1))]
m4_Prefix,
[m4_Separator])[]dnl
m4_defn([m4_Word])[]dnl
])
+# m4_qlen(STRING)
+# ---------------
+# Expands to the length of STRING after autom4te converts all quadrigraphs.
+m4_define([m4_qlen],
+[m4_len(m4_bpatsubsts([[$1]], [@\(<:\|:>\|S|\|%:\)@], [P], [@&t@]))])
+
+
+# m4_qdelta(STRING)
+# -----------------
+# Expands to the net change in the length of STRING from autom4te converting the
+# quadrigraphs in STRING. This number is always negative or zero.
+m4_define([m4_qdelta],
+[m4_eval(m4_qlen([$1]) - m4_len([$1]))])
+
+
## ----------------------- ##
-## 10. Number processing. ##
+## 13. Number processing. ##
## ----------------------- ##
# m4_sign(A)
# The sign of the integer A.
m4_define([m4_sign],
[m4_bmatch([$1],
- [^-], -1,
- [^0+], 0,
- 1)])
+ [^-], -1,
+ [^0+], 0,
+ 1)])
# m4_cmp(A, B)
# ------------
-#
-# Compare two integers.
+# Compare two integer expressions.
# A < B -> -1
# A = B -> 0
# A > B -> 1
[$1], [()], [$0((0), [$2])],
[$2], [()], [$0([$1], (0))],
[m4_case(m4_cmp(m4_car$1, m4_car$2),
- -1, -1,
- 1, 1,
- 0, [$0((m4_shift$1), (m4_shift$2))])])])
+ -1, -1,
+ 1, 1,
+ 0, [$0((m4_shift$1), (m4_shift$2))])])])
## ------------------------ ##
-## 11. Version processing. ##
+## 14. Version processing. ##
## ------------------------ ##
# reasonable version numbers and is valid up to `z', no double letters.
m4_define([m4_version_unletter],
[m4_translit(m4_bpatsubsts([$1],
- [\([0-9]+\)\([abcdefghi]\)],
- [m4_eval(\1 + 1).-1.\2],
- [\([0-9]+\)\([jklmnopqrs]\)],
- [m4_eval(\1 + 1).-1.1\2],
- [\([0-9]+\)\([tuvwxyz]\)],
- [m4_eval(\1 + 1).-1.2\2]),
- [abcdefghijklmnopqrstuvwxyz],
- [12345678901234567890123456])])
+ [\([0-9]+\)\([abcdefghi]\)],
+ [m4_eval(\1 + 1).-1.\2],
+ [\([0-9]+\)\([jklmnopqrs]\)],
+ [m4_eval(\1 + 1).-1.1\2],
+ [\([0-9]+\)\([tuvwxyz]\)],
+ [m4_eval(\1 + 1).-1.2\2]),
+ [abcdefghijklmnopqrstuvwxyz],
+ [12345678901234567890123456])])
# m4_version_compare(VERSION-1, VERSION-2)
# 1 if >
m4_define([m4_version_compare],
[m4_list_cmp((m4_split(m4_version_unletter([$1]), [\.])),
- (m4_split(m4_version_unletter([$2]), [\.])))])
+ (m4_split(m4_version_unletter([$2]), [\.])))])
+
+
+# m4_PACKAGE_NAME
+# m4_PACKAGE_TARNAME
+# m4_PACKAGE_VERSION
+# m4_PACKAGE_STRING
+# m4_PACKAGE_BUGREPORT
+# --------------------
+# If m4sugar/version.m4 is present, then define version strings. This
+# file is optional, provided by Autoconf but absent in Bison.
+m4_sinclude([m4sugar/version.m4])
# m4_version_prereq(VERSION, [IF-OK], [IF-NOT = FAIL])
m4_define([m4_version_prereq],
[m4_if(m4_version_compare(m4_defn([m4_PACKAGE_VERSION]), [$1]), -1,
[m4_default([$3],
- [m4_fatal([Autoconf version $1 or higher is required])])],
+ [m4_fatal([Autoconf version $1 or higher is required],
+ 63)])],
[$2])[]dnl
])
## ------------------- ##
-## 12. File handling. ##
+## 15. File handling. ##
## ------------------- ##
# It is a real pity that M4 comes with no macros to bind a diversion
# to a file. So we have to deal without, which makes us a lot more
-# fragile that we should.
+# fragile than we should.
# m4_file_append(FILE-NAME, CONTENT)
## ------------------------ ##
-## 13. Setting M4sugar up. ##
+## 16. Setting M4sugar up. ##
## ------------------------ ##
# m4_init
# -------
+# Initialize the m4sugar language.
m4_define([m4_init],
[# All the M4sugar macros start with `m4_', except `dnl' kept as is
# for sake of simplicity.
# Check the divert push/pop perfect balance.
m4_wrap([m4_ifdef([_m4_divert_diversion],
- [m4_fatal([$0: unbalanced m4_divert_push:]
-m4_defn([m4_divert_stack]))])[]])
+ [m4_fatal([$0: unbalanced m4_divert_push:]_m4_divert_n_stack)])[]])
m4_divert_push([KILL])
m4_wrap([m4_divert_pop([KILL])[]])
projects / bison.git / blobdiff