Make "err" a weak keyword;

that is, it will be overriden by any sub named "err", except when
really an operator is expected at this point. ([perl #32347])

p4raw-id: //depot/perl@23519

diff --git a/t/op/dor.t b/t/op/dor.t
index 8740a5c..079631a 100644 (file)
--- a/t/op/dor.t
+++ b/t/op/dor.t
@@ -10,7 +10,7 @@ BEGIN {
 package main;
 require './test.pl';
 
-plan( tests => 35 );
+plan( tests => 41 );
 
 my($x);
 
@@ -82,3 +82,15 @@ like( $@, qr/^Search pattern not terminated/ );
 is(0 // 2, 0,          '       // : left-hand operand not optimized away');
 is('' // 2, '',                '       // : left-hand operand not optimized away');
 is(undef // 2, 2,      '       // : left-hand operand optimized away');
+
+# [perl #32347] err should be a weak keyword
+
+package weakerr;
+
+sub err { "<@_>" }
+::is( (shift() err 42), 42,    'err as an operator' );
+::is( (shift err 42), 42,      'err as an operator, with ambiguity' );
+::is( (err 2), "<2>",          'err as a function without parens' );
+::is( err(2, 3), "<2 3>",      'err as a function with parens' );
+::is( err(), "<>",             'err as a function without arguments' );
+::is( err, "<>",               'err as a function without parens' );

diff --git a/toke.c b/toke.c
index 7c9d88f..a7a9068 100644 (file)
--- a/toke.c
+++ b/toke.c
@@ -4037,6 +4037,16 @@ Perl_yylex(pTHX)
            {
                tmp = 0;                /* any sub overrides "weak" keyword */
            }
+           else if (gv && !gvp
+                   && tmp == -KEY_err
+                   && GvCVu(gv)
+                   && PL_expect != XOPERATOR
+                   && PL_expect != XTERMORDORDOR)
+           {
+               /* any sub overrides the "err" keyword, except when really an
+                * operator is expected */
+               tmp = 0;
+           }
            else {                      /* no override */
                tmp = -tmp;
                if (tmp == KEY_dump && ckWARN(WARN_MISC)) {