[SCM] GNU M4 source repository branch, master, updated. cvs-readonly-64-g06991b5

[Eric Blake]

This is an automated email from the git hooks/post-receive script. It was
generated because a ref change was pushed to the repository containing
the project "GNU M4 source repository".

http://git.sv.gnu.org/gitweb/?p=m4.git;a=commitdiff;h=06991b51ef43dcbafa3d878b2beefd1dcc00adc0

The branch, master has been updated
       via  06991b51ef43dcbafa3d878b2beefd1dcc00adc0 (commit)
      from  5d083e4726ed578b093aaf82e2a5a542f5815dcd (commit)

Those revisions listed above that are new to this repository have
not appeared on any other notification email; so we list those
revisions in full, below.

- Log -----------------------------------------------------------------
commit 06991b51ef43dcbafa3d878b2beefd1dcc00adc0
Author: Eric Blake <address@hidden>
Date:   Sat Feb 16 14:39:41 2008 -0700

    Add regression test for multi-character quote recursion.
    
    * examples/foreach2.m4: Use $0 rather than spelling out name.
    * examples/foreachq2.m4: Likewise.
    * examples/forloop2.m4: Likewise.
    * examples/hanoi.m4: Likewise.
    * examples/trace.m4: Likewise.
    * doc/m4.texinfo (Improved forloop): Document advantage of $0.
    (Improved foreach): Adjust dump from file.
    
    Signed-off-by: Eric Blake <address@hidden>

-----------------------------------------------------------------------

Summary of changes:
 ChangeLog             |    9 +++++++++
 doc/m4.texinfo        |   48 +++++++++++++++++++++++++++++++++++++++++++++---
 examples/foreach2.m4  |    2 +-
 examples/foreachq2.m4 |    2 +-
 examples/forloop2.m4  |    2 +-
 examples/hanoi.m4     |    4 ++--
 examples/trace.m4     |    4 ++--
 7 files changed, 61 insertions(+), 10 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index d0ba987..6a89c56 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,14 @@
 2008-02-16  Eric Blake  <address@hidden>
 
+       Add regression test for multi-character quote recursion.
+       * examples/foreach2.m4: Use $0 rather than spelling out name.
+       * examples/foreachq2.m4: Likewise.
+       * examples/forloop2.m4: Likewise.
+       * examples/hanoi.m4: Likewise.
+       * examples/trace.m4: Likewise.
+       * doc/m4.texinfo (Improved forloop): Document advantage of $0.
+       (Improved foreach): Adjust dump from file.
+
        Stage 15: return argv refs back to collect_arguments.
        Collect an entire $@ reference at once rather than one argument at
        a time, outside of quotes (but inside quotes, $@ is still
diff --git a/doc/m4.texinfo b/doc/m4.texinfo
index c313984..571c0dc 100644
--- a/doc/m4.texinfo
+++ b/doc/m4.texinfo
@@ -8256,7 +8256,7 @@ undivert(`forloop2.m4')dnl
 @result{}#   performs sanity check that FROM is larger than TO
 @result{}#   allows complex numerical expressions in TO and FROM
 @result{}define(`forloop', `ifelse(eval(`($3) >= ($2)'), `1',
address@hidden  `pushdef(`$1', eval(`$2'))_forloop(`$1',
address@hidden  `pushdef(`$1', eval(`$2'))_$0(`$1',
 @result{}    eval(`$3'), `$4')popdef(`$1')')')
 @result{}define(`_forloop',
 @result{}  `$3`'ifelse(indir(`$1'), `$2', `',
@@ -8275,6 +8275,48 @@ forloop(`i', `a', `b', `non-numeric bounds')
 @result{}
 @end example
 
+One other change to notice is that the improved version used @samp{_$0}
+rather than @samp{_foreach} to invoke the helper routine.  In general,
+this is a good practice to follow, because then the set of macros can be
+uniformly transformed.  The following example shows a transformation
+that doubles the current quoting and appends a suffix @samp{2} to each
+transformed macro.  If @code{foreach} refers to the literal
address@hidden, then @code{foreach2} invokes @code{_foreach} instead of
+the intended @code{_foreach2}, and the mixing of quoting paradigms leads
+to an infinite recursion loop in this example.
+
address@hidden options: -L9
address@hidden status: 1
address@hidden examples
address@hidden
+$ @kbd{m4 -d -L 9 -I examples}
+define(`arg1', `$1')include(`forloop2.m4')include(`quote.m4')
address@hidden
+define(`double', `define(`$1'`2',
+  arg1(patsubst(dquote(defn(`$1')), `[`']', `\&\&')))')
address@hidden
+double(`forloop')double(`_forloop')defn(`forloop2')
address@hidden(eval(``($3) >= ($2)''), ``1'',
address@hidden  ``pushdef(``$1'', eval(``$2''))_$0(``$1'',
address@hidden    eval(``$3''), ``$4'')popdef(``$1'')'')
+forloop(i, 1, 5, `ifelse(')forloop(i, 1, 5, `)')
address@hidden
+changequote(`[', `]')changequote([``], [''])
address@hidden
+forloop2(i, 1, 5, ``ifelse('')forloop2(i, 1, 5, ``)'')
address@hidden
+changequote`'include(`forloop.m4')
address@hidden
+double(`forloop')double(`_forloop')defn(`forloop2')
address@hidden(``$1'', ``$2'')_forloop($@@)popdef(``$1'')
+forloop(i, 1, 5, `ifelse(')forloop(i, 1, 5, `)')
address@hidden
+changequote(`[', `]')changequote([``], [''])
address@hidden
+forloop2(i, 1, 5, ``ifelse('')forloop2(i, 1, 5, ``)'')
address@hidden:stdin:12: recursion limit of 9 exceeded, use -L<N> to change it
address@hidden example
+
 Of course, it is possible to make even more improvements, such as
 adding an optional step argument, or allowing iteration through
 descending sequences.  @acronym{GNU} Autoconf provides some of these
@@ -8339,7 +8381,7 @@ undivert(`foreachq2.m4')dnl
 @result{}divert(`-1')
 @result{}# foreachq(x, `item_1, item_2, ..., item_n', stmt)
 @result{}#   quoted list, improved version
address@hidden(`foreachq', `pushdef(`$1')_foreachq($@@)popdef(`$1')')
address@hidden(`foreachq', `pushdef(`$1')_$0($@@)popdef(`$1')')
 @result{}define(`_arg1q', ``$1'')
 @result{}define(`_rest', `ifelse(`$#', `1', `', `dquote(shift($@@))')')
 @result{}define(`_foreachq', `ifelse(`$2', `', `',
@@ -8436,7 +8478,7 @@ undivert(`foreach2.m4')dnl
 @result{}divert(`-1')
 @result{}# foreach(x, (item_1, item_2, ..., item_n), stmt)
 @result{}#   parenthesized list, improved version
address@hidden(`foreach', `pushdef(`$1')_foreach(`$1',
address@hidden(`foreach', `pushdef(`$1')_$0(`$1',
 @result{}  (dquote(dquote_elt$2)), `$3')popdef(`$1')')
 @result{}define(`_arg1', `$1')
 @result{}define(`_foreach', `ifelse(`$2', `(`')', `',
diff --git a/examples/foreach2.m4 b/examples/foreach2.m4
index 4acf0c2..74d00fb 100644
--- a/examples/foreach2.m4
+++ b/examples/foreach2.m4
@@ -2,7 +2,7 @@ include(`quote.m4')dnl
 divert(`-1')
 # foreach(x, (item_1, item_2, ..., item_n), stmt)
 #   parenthesized list, improved version
-define(`foreach', `pushdef(`$1')_foreach(`$1',
+define(`foreach', `pushdef(`$1')_$0(`$1',
   (dquote(dquote_elt$2)), `$3')popdef(`$1')')
 define(`_arg1', `$1')
 define(`_foreach', `ifelse(`$2', `(`')', `',
diff --git a/examples/foreachq2.m4 b/examples/foreachq2.m4
index 345ddfe..f57d3ed 100644
--- a/examples/foreachq2.m4
+++ b/examples/foreachq2.m4
@@ -2,7 +2,7 @@ include(`quote.m4')dnl
 divert(`-1')
 # foreachq(x, `item_1, item_2, ..., item_n', stmt)
 #   quoted list, improved version
-define(`foreachq', `pushdef(`$1')_foreachq($@)popdef(`$1')')
+define(`foreachq', `pushdef(`$1')_$0($@)popdef(`$1')')
 define(`_arg1q', ``$1'')
 define(`_rest', `ifelse(`$#', `1', `', `dquote(shift($@))')')
 define(`_foreachq', `ifelse(`$2', `', `',
diff --git a/examples/forloop2.m4 b/examples/forloop2.m4
index f1bdf0e..41e0e16 100644
--- a/examples/forloop2.m4
+++ b/examples/forloop2.m4
@@ -4,7 +4,7 @@ divert(`-1')
 #   performs sanity check that FROM is larger than TO
 #   allows complex numerical expressions in TO and FROM
 define(`forloop', `ifelse(eval(`($3) >= ($2)'), `1',
-  `pushdef(`$1', eval(`$2'))_forloop(`$1',
+  `pushdef(`$1', eval(`$2'))_$0(`$1',
     eval(`$3'), `$4')popdef(`$1')')')
 define(`_forloop',
   `$3`'ifelse(indir(`$1'), `$2', `',
diff --git a/examples/hanoi.m4 b/examples/hanoi.m4
index c4a7c14..32fd8a4 100644
--- a/examples/hanoi.m4
+++ b/examples/hanoi.m4
@@ -6,10 +6,10 @@ define(`move', `Move one disk from `$1' to `$2'.
 
 # _hanoi (cnt, from, to, aux)
 define(`_hanoi', `ifelse(eval(`$1'<=1), 1, `move($2, $3)',
-`_hanoi(decr($1), $2, $4, $3)move($2, $3)_hanoi(decr($1), $4, $3, $2)')')
+`$0(decr($1), $2, $4, $3)move($2, $3)$0(decr($1), $4, $3, $2)')')
 
 # hanoi (cnt)
-define(`hanoi', `_hanoi(`$1', source, destination, auxilliary)')
+define(`hanoi', `_$0(`$1', source, destination, auxilliary)')
 
 # traceon(`move', `_hanoi', `decr')
 divert`'dnl
diff --git a/examples/trace.m4 b/examples/trace.m4
index a79dbcd..92ce981 100644
--- a/examples/trace.m4
+++ b/examples/trace.m4
@@ -6,10 +6,10 @@ define(`move', `Move one disk from `$1' to `$2'.
 
 # _hanoi (cnt, from, to, aux)
 define(`_hanoi', `ifelse(eval(`$1'<=1), 1, `move($2, $3)',
-`_hanoi(decr($1), $2, $4, $3)move($2, $3)_hanoi(decr($1), $4, $3, $2)')')
+`$0(decr($1), $2, $4, $3)move($2, $3)$0(decr($1), $4, $3, $2)')')
 
 # hanoi (cnt)
-define(`hanoi', `_hanoi(`$1', source, destination, auxilliary)')
+define(`hanoi', `_$0(`$1', source, destination, auxilliary)')
 divert`'dnl
 
 # Debugmode t


hooks/post-receive
--
GNU M4 source repository