make failed matches return empty list in list context

p4raw-id: //depot/perl@1542

diff --git a/pod/perlop.pod b/pod/perlop.pod
index 8b73629..c7209fa 100644 (file)
--- a/pod/perlop.pod
+++ b/pod/perlop.pod
@@ -774,11 +774,11 @@ I<successfully> matched regular expression is used instead.
 
 If the C</g> option is not used, C<m//> in a list context returns a
 list consisting of the subexpressions matched by the parentheses in the
-pattern, i.e., (C<$1>, C<$2>, C<$3>...).  (Note that here
-C<$1> etc. are also set, and
-that this differs from Perl 4's behavior.)  If there are no parentheses,
-the return value is the list C<(1)> for success or C<('')> upon failure.
-With parentheses, C<()> is returned upon failure.
+pattern, i.e., (C<$1>, C<$2>, C<$3>...).  (Note that here C<$1> etc. are
+also set, and that this differs from Perl 4's behavior.)  When there are
+no parentheses in the pattern, the return value is the list C<(1)> for
+success.  With or without parentheses, an empty list is returned upon
+failure.
 
 Examples:
 

diff --git a/pp_hot.c b/pp_hot.c
index 4fe40cc..3ecb5b3 100644 (file)
--- a/pp_hot.c
+++ b/pp_hot.c
@@ -853,8 +853,6 @@ PP(pp_match)
            }
        }
     }
-    if (!rx->nparens && !global)
-       gimme = G_SCALAR;                       /* accidental array context? */
     safebase = (((gimme == G_ARRAY) || global || !rx->nparens)
                && !sawampersand);
     safebase = safebase ? 0  : REXEC_COPY_STR ;
@@ -958,6 +956,8 @@ play_it_again:
            PUTBACK;                    /* EVAL blocks may use stack */
            goto play_it_again;
        }
+       else if (!iters)
+           XPUSHs(&sv_yes);
        LEAVE_SCOPE(oldsave);
        RETURN;
     }

diff --git a/t/op/pat.t b/t/op/pat.t
index cbd5f89..ef014f2 100755 (executable)
--- a/t/op/pat.t
+++ b/t/op/pat.t
@@ -4,9 +4,7 @@
 # the format supported by op/regexp.t.  If you want to add a test
 # that does fit that format, add it to op/re_tests, not here.
 
-# $RCSfile: pat.t,v $$Revision: 4.1 $$Date: 92/08/07 18:28:12 $
-
-print "1..135\n";
+print "1..139\n";
 
 BEGIN {
     chdir 't' if -d 't';
@@ -560,3 +558,26 @@ my $for_future = make_must_warn('reserved for future extensions');
 &$for_future('q(a:[b]:) =~ /[x[:foo:]]/');
 &$for_future('q(a=[b]=) =~ /[x[=foo=]]/');
 &$for_future('q(a.[b].) =~ /[x[.foo.]]/');
+
+# test if failure of patterns returns empty list
+$_ = 'aaa';
+@_ = /bbb/;
+print "not " if @_;
+print "ok $test\n";
+$test++;
+
+@_ = /bbb/g;
+print "not " if @_;
+print "ok $test\n";
+$test++;
+
+@_ = /(bbb)/;
+print "not " if @_;
+print "ok $test\n";
+$test++;
+
+@_ = /(bbb)/g;
+print "not " if @_;
+print "ok $test\n";
+$test++;
+