warning for split(/.../g, ...);

Message-ID: <20020401182201.21189.qmail@plover.com>

p4raw-id: //depot/perl@15663

diff --git a/op.c b/op.c
index 9b07a2f..e7f1042 100644 (file)
--- a/op.c
+++ b/op.c
@@ -6658,6 +6658,10 @@ Perl_ck_split(pTHX_ OP *o)
     kid->op_type = OP_PUSHRE;
     kid->op_ppaddr = PL_ppaddr[OP_PUSHRE];
     scalar(kid);
+    if (ckWARN(WARN_REGEXP) && ((PMOP *)kid)->op_pmflags & PMf_GLOBAL) {
+      Perl_warner(aTHX_ packWARN(WARN_REGEXP),
+                  "Use of /g modifier is meaningless in split");
+    }
 
     if (!kid->op_sibling)
        append_elem(OP_SPLIT, o, newDEFSVOP());

diff --git a/pod/perldelta.pod b/pod/perldelta.pod
index 27823a7..f5d98ef 100644 (file)
--- a/pod/perldelta.pod
+++ b/pod/perldelta.pod
@@ -559,8 +559,12 @@ The command-line options -s and -F are now recognized on the shebang
 
 Use of the C</c> match modifier without an accompanying C</g> modifier
 elicits a new warning: C<Use of /c modifier is meaningless without /g>.
+
 Use of C</c> in substitutions, even with C</g>, elicits 
-C<Use of /c modifier is meaningless in s///>.
+C<Use of /c modifier is meaningless in s///>.  
+
+Use of C</g> with C<split> elicits <Use of /g modifier is meaningless
+in split>.
 
 =back
 

diff --git a/pod/perldiag.pod b/pod/perldiag.pod
index 35f26c4..08f342a 100644 (file)
--- a/pod/perldiag.pod
+++ b/pod/perldiag.pod
@@ -3996,6 +3996,12 @@ modifier is not presently meaningful in substitutions.
 use the /g modifier.  Currently, /c is meaningful only when /g is
 used.  (This may change in the future.)
 
+=item Use of /g modifier is meaningless in split
+
+(W regexp) You used the /g modifier on the pattern for a C<split>
+operator.  Since C<split> always tries to match the pattern
+repeatedly, the C</g> has no effect.
+
 =item Use of *glob{FILEHANDLE} is deprecated
 
 (D deprecated) You are now encouraged to use the shorter *glob{IO} form

diff --git a/t/lib/warnings/op b/t/lib/warnings/op
index ff00dcd..7833562 100644 (file)
--- a/t/lib/warnings/op
+++ b/t/lib/warnings/op
@@ -111,6 +111,8 @@
 
     Package `%s' not found (did you use the incorrect case?)
 
+    Use of /g modifier is meaningless in split
+
     Mandatory Warnings 
     ------------------
     Prototype mismatch:                [cv_ckproto]
@@ -952,3 +954,12 @@ EXPECT
 Use of "package" with no arguments is deprecated at - line 3.
 Global symbol "BEGIN" requires explicit package name at - line 4.
 BEGIN not safe after errors--compilation aborted at - line 4.
+########
+# op.c
+# 20020401 mjd@plover.com at suggestion of jfriedl@yahoo.com
+use warnings 'regexp';
+split /blah/g, "blah";
+no warnings 'regexp';
+split /blah/g, "blah";
+EXPECT
+Use of /g modifier is meaningless in split at - line 4.