From: Stepan Kasal <kasal@ucw.cz>
Date: Thu, 27 Oct 2005 13:34:07 +0000 (+0000)
Subject: * HACKING: Update note about use of `$#' in m4 macros.
X-Git-Tag: release-2-1b~445
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6e177b308758d5cf839d3266bbe2d098b1d4d730;p=thirdparty%2Flibtool.git

* HACKING: Update note about use of `$#' in m4 macros.
---

diff --git a/ChangeLog b/ChangeLog
index 6610ca48b..27487ac8b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2005-10-27  Stepan Kasal  <kasal@ucw.cz>
+
+	* HACKING: Update note about use of `$#' in m4 macros.
+
 2005-10-27  Ralf Wildenhues  <Ralf.Wildenhues@gmx.de>
 
 	* tests/tagtrace.test: Allow `$AUTOCONF' to contain arguments.
diff --git a/HACKING b/HACKING
index 569a18c21..c1f9ecdf6 100644
--- a/HACKING
+++ b/HACKING
@@ -241,8 +241,11 @@ yyyy-mm-dd  Name of Author  <email@address>  (tiny change)
    $ECHO ".."		for strings without leading hyphen,
    $ECHO "X.." | $Xsed	otherwise.
 
-* Do not use the number of macro arguments `$#' in public macros;
-  AU_ALIAS may change it.
+* The Autoconf manual says that giving an empty parameter is equivalent
+  to not giving it at all.  (In particular, the Autoconf manual doesn't
+  explain that "FOO()" is calling macro FOO with one empty parameter.)
+  To prevent misunderstanding, we should use m4_ifval to check whether
+  a parameter is empty, and not $# to check for the number of parameters.
 
 
 9. Abstraction layers in libltdl