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+# init-package-version.m4 serial 1 (gettext-0.18)
+dnl Copyright (C) 1992-2009 Free Software Foundation, Inc.
+dnl This file is free software, distributed under the terms of the GNU
+dnl General Public License. As a special exception to the GNU General
+dnl Public License, this file may be distributed as part of a program
+dnl that contains a configuration script generated by Autoconf, under
+dnl the same distribution terms as the rest of that program.
+
+# Make it possible to pass version numbers extracted from a file in
+# $(srcdir) to autoconf.
+#
+# Autoconf insists on passing the package name and version number to
+# every generated .h file and every Makefile. This was a reasonable
+# design at times when a version number was changed only once a month.
+# Nowadays, people often assign a new version number once a week, or
+# even change it each time a 'git' commit is made. Regenerating all
+# the files that depend on configure.ac (aclocal.m4, configure,
+# config.status, config.h, all Makefiles) may take 15 minutes. These
+# delays can severely hamper development.
+#
+# An alternative is to store the version number in a file in $(srcdir)
+# that is separate from configure.ac. It can be a data file, a shell
+# script, a .m4 file, or other. The essential point is that the maintainer
+# is responsible for creating Makefile dependencies to this version file
+# for every file that needs to be rebuilt when the version changes. This
+# typically includes
+# - distributable documentation files that carry the version number,
+# but does not include
+# - aclocal.m4, configure, config.status, config.h, all Makefiles,
+# - executables.
+#
+# autoconf and automake make it hard to follow this approach:
+#
+# - If AC_INIT is used with arguments, there is a chicken-and-egg problem:
+# The arguments need to be read from a file in $(srcdir). The location
+# of $(srcdir) is only determined by AC_CONFIG_SRCDIR. AC_CONFIG_SRCDIR
+# can only appear after AC_INIT (otherwise aclocal gives an error:
+# "error: m4_defn: undefined macro: _m4_divert_diversion").
+# Furthermore, the arguments passed to AC_INIT must be literals; for
+# example, the assignment to PACKAGE_VERSION looks like this:
+# [PACKAGE_VERSION=']AC_PACKAGE_VERSION[']
+#
+# - If AC_INIT is used without arguments:
+# Automake provides its own variables, PACKAGE and VERSION, and uses them
+# instead of PACKAGE_NAME and PACKAGE_VERSION that come from Autoconf.
+# - If AM_INIT_AUTOMAKE is used with two arguments, automake options
+# like 'silent-rules' cannot be specified.
+# - If AM_INIT_AUTOMAKE is used in its one-argument form or without
+# arguments at all, it triggers an error
+# "error: AC_INIT should be called with package and version arguments".
+# - If AM_INIT_AUTOMAKE is used in its one-argument form or without
+# arguments at all, and _AC_INIT_PACKAGE is used before it, with
+# the package and version number from the file as arguments, we get
+# a warning: "warning: AC_INIT: not a literal: $VERSION_NUMBER".
+# The arguments passed to _AC_INIT_PACKAGE must be literals.
+#
+# With the macro defined in this file, the approach can be coded like this:
+#
+# AC_INIT
+# AC_CONFIG_SRCDIR(WITNESS)
+# . $srcdir/../version.sh
+# gl_INIT_PACKAGE(PACKAGE, $VERSION_NUMBER)
+# AM_INIT_AUTOMAKE([OPTIONS])
+
+# gl_INIT_PACKAGE(PACKAGE-NAME, VERSION)
+# --------------------------------------
+# followed by an AM_INIT_AUTOMAKE invocation,
+# is like calling AM_INIT_AUTOMAKE(PACKAGE-NAME, VERSION)
+# except that it can use computed non-literal arguments.
+AC_DEFUN([gl_INIT_PACKAGE],
+[
+ AC_BEFORE([$0], [AM_INIT_AUTOMAKE])
+ dnl Redefine AM_INIT_AUTOMAKE.
+ m4_define([gl_AM_INIT_AUTOMAKE],
+ m4_bpatsubst(m4_dquote(
+ m4_bpatsubst(m4_dquote(
+ m4_bpatsubst(m4_dquote(
+ m4_defn([AM_INIT_AUTOMAKE])),
+ [AC_PACKAGE_NAME], [gl_INIT_DUMMY])),
+ [AC_PACKAGE_TARNAME], [gl_INIT_DUMMY])),
+ [AC_PACKAGE_VERSION], [gl_INIT_DUMMY])
+ [AC_SUBST([PACKAGE], [$1])
+ AC_SUBST([VERSION], [$2])
+ ])
+ m4_define([AM_INIT_AUTOMAKE],
+ m4_defn([gl_RPL_INIT_AUTOMAKE]))
+])
+m4_define([gl_INIT_DUMMY], [])
+AC_DEFUN([gl_RPL_INIT_AUTOMAKE], [
+ m4_ifval([$2],
+ [m4_fatal([After gl_INIT_PACKAGE, the two-argument form of AM_INIT_AUTOMAKE cannot be used.])])
+ gl_AM_INIT_AUTOMAKE([$1 no-define])
+ m4_if(m4_index([ $1 ], [ no-define ]), [-1],
+ [AC_DEFINE_UNQUOTED(PACKAGE, "$PACKAGE", [Name of package])
+ AC_DEFINE_UNQUOTED(VERSION, "$VERSION", [Version number of package])
+ ])
+])