configure: Improve detection of a suitable Lout.

* configure.ac: Use `LOUT_PROGRAM' and `LOUT_REQUIRED_PACKAGE'.

* m4/lout.m4: New.

4 files changed, 64 insertions, 4 deletions

diff --git a/.gitignore b/.gitignore
index 983b675..03d7b28 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,7 +5,6 @@ Makefile.in
 aclocal.m4
 autom4te.cache
 build-aux/*
-m4/*
 config.cache
 config.log
 config.status
diff --git a/configure.ac b/configure.ac
index c7e9df4..a2de438 100644
--- a/configure.ac
+++ b/configure.ac
@@ -47,9 +47,8 @@ GUILE_MODULE_REQUIRED([srfi srfi-35])
 GUILE_MODULE_REQUIRED([srfi srfi-37])
 
 
-# Look for Lout.
-AC_PATH_PROG([LOUT], [lout])
-AM_CONDITIONAL([HAVE_LOUT], [test "x$LOUT" != "x"])
+# Look for a suitable version of Lout.
+LOUT_PROGRAM([LOUT_REQUIRED_PACKAGE([math])])
 
 # Look for `ps2pdf' from GhostScript.
 AC_PATH_PROG([PS2PDF], [ps2pdf])
diff --git a/m4/.gitignore b/m4/.gitignore
new file mode 100644
index 0000000..1edc327
--- /dev/null
+++ b/m4/.gitignore
@@ -0,0 +1,8 @@
+gettext.m4
+iconv.m4
+lib-ld.m4
+lib-link.m4
+lib-prefix.m4
+nls.m4
+po.m4
+progtest.m4
diff --git a/m4/lout.m4 b/m4/lout.m4
new file mode 100644
index 0000000..442b168
--- /dev/null
+++ b/m4/lout.m4
@@ -0,0 +1,54 @@
+dnl Copyright (C) 2008  Ludovic Courtès <ludo@gnu.org>
+dnl
+dnl This file is free software; you can redistribute it and/or
+dnl modify it under the terms of the GNU Lesser General Public
+dnl License as published by the Free Software Foundation; either
+dnl version 2.1 of the License, or (at your option) any later version.
+dnl 
+dnl This file is distributed in the hope that it will be useful,
+dnl but WITHOUT ANY WARRANTY; without even the implied warranty of
+dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+dnl Lesser General Public License for more details.
+dnl 
+dnl You should have received a copy of the GNU Lesser General Public
+dnl License along with this file; if not, write to the Free Software
+dnl Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+
+
+dnl Usage: LOUT_PROGRAM [ACTION-IF-FOUND] [ACTION-IF-NOT-FOUND]
+dnl
+dnl Look for Lout.  If found, define the `LOUT' environment variable
+dnl containing its path, define Automake condition `HAVE_LOUT', and
+dnl run ACTION-IF-FOUND.  If not found, run ACTION-IF-NOT-FOUND.
+AC_DEFUN([LOUT_PROGRAM],
+[
+  AC_PATH_PROG([LOUT], [lout])
+  AM_CONDITIONAL([HAVE_LOUT], [test "x$LOUT" != "x"])
+  if test "x$LOUT" != "x"; then
+    :
+    $1
+  else
+    :
+    $2
+  fi
+])
+
+dnl Usage: LOUT_REQUIRED_PACKAGE PACKAGE
+dnl
+dnl Makes sure Lout has package PACKAGE.
+AC_DEFUN([LOUT_REQUIRED_PACKAGE],
+[
+  AC_MSG_CHECKING([whether Lout has package `$1'])
+  echo "@SysInclude { $1 }" | "$LOUT" 2> /dev/null
+  if test "$?" -eq 0; then
+    AC_MSG_RESULT([yes])
+  else
+    AC_MSG_RESULT([no])
+    AC_MSG_ERROR([Your installation of Lout doesn't have package `$1', please upgrade.])
+  fi
+])
+
+dnl Local Variables:
+dnl mode: autoconf
+dnl coding: utf-8
+dnl End