FYI: Autoconf internals

[Akim Demaille]

Do not use m4_patsubst and m4_regexp, as they are reserved for future
use with ERE macros in M4 1.5.  patsubst and regexp have always been
kept.

AC_PLAIN_SCRIPT is an internal detail, it has never been published.

BTW, note that AM_DIRNAME is typically something which will be moved
to Autoconf.

Index: ChangeLog
from  Akim Demaille  <address@hidden>

        Do not use Autoconf internals.

        * tests/dirname.test: Don't use AC_PLAIN_SCRIPT.
        * m4/header.m4 (_AM_DIRNAME): Use regexp and patsubst, not
        m4_regexp and m4_patsubst, since the latter are reserved for ERE
        macro in GNU M4 1.5.

Index: m4/header.m4
===================================================================
RCS file: /cvs/automake/automake/m4/header.m4,v
retrieving revision 1.10
diff -u -u -r1.10 header.m4
--- m4/header.m4 2001/09/27 09:01:05 1.10
+++ m4/header.m4 2001/10/10 13:01:01
@@ -47,11 +47,11 @@
 # -----------------
 # Like AS_DIRNAME, only do it during macro expansion
 AC_DEFUN([_AM_DIRNAME],
-       [m4_if(m4_regexp([$1], [^.*[^/]//*[^/][^/]*/*$]), -1,
-             m4_if(m4_regexp([$1], [^//\([^/]\|$\)]), -1,
-                   m4_if(m4_regexp([$1], [^/.*]), -1,
+       [m4_if(regexp([$1], [^.*[^/]//*[^/][^/]*/*$]), -1,
+             m4_if(regexp([$1], [^//\([^/]\|$\)]), -1,
+                   m4_if(regexp([$1], [^/.*]), -1,
                          [.],
-                         m4_patsubst([$1], [^\(/\).*], [\1])),
-                   m4_patsubst([$1], [^\(//\)\([^/].*\|$\)], [\1])),
-             m4_patsubst([$1], [^\(.*[^/]\)//*[^/][^/]*/*$], [\1]))[]dnl
+                         patsubst([$1], [^\(/\).*], [\1])),
+                   patsubst([$1], [^\(//\)\([^/].*\|$\)], [\1])),
+             patsubst([$1], [^\(.*[^/]\)//*[^/][^/]*/*$], [\1]))[]dnl
 ]) # _AM_DIRNAME
Index: tests/dirname.test
===================================================================
RCS file: /cvs/automake/automake/tests/dirname.test,v
retrieving revision 1.3
diff -u -u -r1.3 dirname.test
--- tests/dirname.test 2001/07/25 15:27:36 1.3
+++ tests/dirname.test 2001/10/10 13:01:01
@@ -5,7 +5,7 @@
 . $srcdir/defs || exit 1
 
 cat > configure.in << 'END'
-AC_PLAIN_SCRIPT
+AC_INIT
 echo "1 /a/path/to/a/file      = _AM_DIRNAME([/a/path/to/a/file])"
 echo "2 another/path/to/a/file = _AM_DIRNAME([another/path/to/a/file])"
 echo "3 file                   = _AM_DIRNAME([file])"
@@ -19,12 +19,9 @@
 $needs_autoconf
 
 $ACLOCAL || exit 1
-$AUTOCONF || exit 1
+# fail gracefully if autoconf didn't support support our regexps anyhow
+$AUTOCONF || exit 77
 
-# fail gracefully if autoconf didn't support AC_PLAIN_SCRIPT, because it won't
-# support our regexps anyhow
-test -s configure || exit 77
-
 $SHELL ./configure >got || exit 1
 
 cat >wanted <<EOF
@@ -40,4 +37,3 @@
 diff wanted got || exit 1
 
 exit 0
-