From: Paul Eggert <eggert@cs.ucla.edu>
Date: Wed, 5 Oct 2005 21:27:43 +0000 (+0000)
Subject: * lib/m4sugar/m4sugar.m4 (_m4_map): New macro.
X-Git-Tag: AUTOCONF-2.59c~238
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=cf3b3ede9210fa51eaab4d39d1d75ffa87800ab6;p=thirdparty%2Fautoconf.git

* lib/m4sugar/m4sugar.m4 (_m4_map): New macro.
(m4_map, m4_map_sep): Use it.  Handle the empty list correctly.
---

diff --git a/ChangeLog b/ChangeLog
index 0c603328c..29de880ba 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2005-10-05  Paul Eggert  <eggert@cs.ucla.edu>
+
+	* lib/m4sugar/m4sugar.m4 (_m4_map): New macro.
+	(m4_map, m4_map_sep): Use it.  Handle the empty list correctly.
+
 2005-10-04  Stepan Kasal  <kasal@ucw.cz>
 
 	* lib/autotest/general.m4 (AT_INIT): Really make the subtree writable
diff --git a/lib/m4sugar/m4sugar.m4 b/lib/m4sugar/m4sugar.m4
index 706a3a5f1..ad184c25f 100644
--- a/lib/m4sugar/m4sugar.m4
+++ b/lib/m4sugar/m4sugar.m4
@@ -398,8 +398,11 @@ m4_define([m4_cdr],
 # of LIST (which can be lists themselves, for multiple arguments MACROs).
 m4_define([m4_fst], [$1])
 m4_define([m4_map],
+[m4_if([$2], [[]], [],
+       [_m4_map([$1], [$2])])])
+m4_define([_m4_map],
 [m4_ifval([$2],
-	  [$1(m4_fst($2))[]m4_map([$1], m4_cdr($2))])])
+	  [$1(m4_fst($2))[]_m4_map([$1], m4_cdr($2))])])
 
 
 # m4_map_sep(MACRO, SEPARATOR, LIST)
@@ -408,8 +411,8 @@ m4_define([m4_map],
 # are the elements of LIST (which can be lists themselves, for multiple
 # arguments MACROs).
 m4_define([m4_map_sep],
-[m4_ifval([$3],
-	  [$1(m4_fst($3))[]m4_map([$2[]$1], m4_cdr($3))])])
+[m4_if([$3], [[]], [],
+       [$1(m4_fst($3))[]_m4_map([$2[]$1], m4_cdr($3))])])
 
 
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