FYI: M4sugar doc

[Akim Demaille]

Index: ChangeLog
from  Akim Demaille  <address@hidden>
        * doc/autoconf.texi (Redefined M4 Macros): New.

Index: doc/autoconf.texi
===================================================================
RCS file: /cvs/autoconf/doc/autoconf.texi,v
retrieving revision 1.475
diff -u -u -r1.475 autoconf.texi
--- doc/autoconf.texi 2001/06/23 13:10:32 1.475
+++ doc/autoconf.texi 2001/06/23 15:30:08
@@ -303,6 +303,7 @@
 
 Programming in M4sugar
 
+* Redefined M4 Macros::         M4 builtins changed in M4sugar
 * Forbidden Patterns::          Catching unexpanded macros
 
 Writing Autoconf Macros
@@ -6296,10 +6297,47 @@
 M4sugar''.
 
 @menu
+* Redefined M4 Macros::         M4 builtins changed in M4sugar
 * Forbidden Patterns::          Catching unexpanded macros
 @end menu
 
address@hidden Forbidden Patterns,  , Programming in M4sugar, Programming in 
M4sugar
address@hidden Redefined M4 Macros, Forbidden Patterns, Programming in M4sugar, 
Programming in M4sugar
address@hidden Redefined M4 Macros
+
+All the M4 native macros are moved in the @samp{m4_} pseudo-namespace,
+e.g., M4sugar renames @code{define} as @code{m4_define} etc.  There is
+one exception: @code{dnl} kept its original name, and no @code{m4_dnl}
+is defined.
+
+M4sugar redefines some M4 macros, and made them slightly incompatible
+with their native equivalent.
+
address@hidden m4_defn (@var{macro})
address@hidden defn
+Contrary to the M4 builtin, this macro fails if @var{macro} is not
+defined.  See @code{m4_undefine}.
address@hidden defmac
+
address@hidden m4_undefine (@var{macro})
address@hidden undefine
+Contrary to the M4 builtin, this macro fails if @var{macro} is not
+defined.  Use
+
address@hidden
+m4_ifdef(address@hidden, [m4_undefine(address@hidden)])
address@hidden example
+
address@hidden
+to recover the behavior of the builtin.
address@hidden defmac
+
address@hidden m4_popdef (@var{macro})
address@hidden defn
+Contrary to the M4 builtin, this macro fails if @var{macro} is not
+defined.  See @code{m4_undefine}.
address@hidden defmac
+
address@hidden Forbidden Patterns,  , Redefined M4 Macros, Programming in 
M4sugar
 @subsection Forbidden Patterns
 
 M4sugar provides a means to define suspicious patterns, patterns