Re: [ID 19990830.005] Assigning value of an op on an SV to said SV

To: ilya@math.ohio-state.edu (Ilya Zakharevich)
Cc: perl5-porters@perl.org, cloos@adamsmith.ai
Message-Id: <199909010656.CAA04478@monk.mps.ohio-state.edu>

p4raw-id: //depot/cfgperl@4061

diff --git a/op.c b/op.c
index a371d79..57ff104 100644 (file)
--- a/op.c
+++ b/op.c
@@ -5294,6 +5294,19 @@ Perl_ck_sassign(pTHX_ OP *o)
            {
                return o;
            }
+           if (kid->op_type == OP_JOIN) {
+               /* do_join has problems the arguments coincide with target.
+                  In fact the second argument *can* safely coincide,
+                  but ignore=pessimize this rare occasion. */
+               OP *arg = kLISTOP->op_first->op_sibling; /* Skip PUSHMARK */
+
+               while (arg) {
+                   if (arg->op_type == OP_PADSV
+                       && arg->op_targ == kkid->op_targ)
+                       return o;
+                   arg = arg->op_sibling;
+               }
+           }
            kid->op_targ = kkid->op_targ;
            /* Now we do not need PADSV and SASSIGN. */
            kid->op_sibling = o->op_sibling;    /* NULL */

diff --git a/t/op/join.t b/t/op/join.t
index eec4611..def5a9e 100755 (executable)
--- a/t/op/join.t
+++ b/t/op/join.t
@@ -1,8 +1,6 @@
 #!./perl
 
-# $RCSfile: join.t,v $$Revision: 4.1 $$Date: 92/08/07 18:28:01 $
-
-print "1..3\n";
+print "1..6\n";
 
 @x = (1, 2, 3);
 if (join(':',@x) eq '1:2:3') {print "ok 1\n";} else {print "not ok 1\n";}
@@ -10,3 +8,15 @@ if (join(':',@x) eq '1:2:3') {print "ok 1\n";} else {print "not ok 1\n";}
 if (join('',1,2,3) eq '123') {print "ok 2\n";} else {print "not ok 2\n";}
 
 if (join(':',split(/ /,"1 2 3")) eq '1:2:3') {print "ok 3\n";} else {print "not ok 3\n";}
+
+my $f = 'a';
+$f = join ',', 'b', $f, 'e';
+if ($f eq 'b,a,e') {print "ok 4\n";} else {print "# '$f'\nnot ok 4\n";}
+
+$f = 'a';
+$f = join ',', $f, 'b', 'e';
+if ($f eq 'a,b,e') {print "ok 5\n";} else {print "not ok 5\n";}
+
+$f = 'a';
+$f = join $f, 'b', 'e', 'k';
+if ($f eq 'baeak') {print "ok 6\n";} else {print "# '$f'\nnot ok 6\n";}