Hi Henning, Perl-Monks,

we just encountered the same problem. I think it's a bug in the Perl compiler as constant.pm does not do anything illegal concerning the symbol table.

And just compiling the index function should not have an effect of the contents of the symbol table.

Here's a short script to verify the error. Also includes a Workaround to use the "&" prefix for the constant when used inside the index call.

#!/usr/bin/perl

use strict;
use warnings;

use constant ABC => 'abc';
use constant CDE => 'cde';
use Data::Dumper;

# print the constants value before the sub below has been compiled
# results in $VAR1 = 'abc'
BEGIN {
  print Dumper( ABC );
  print Dumper( CDE );
}

# this is in a sub to show that it's not necessary
# to actually call index to change the constants behaviour
sub some1 { index( shift, ABC ) };

# prefixing the constant with an "&" prevents the error
sub some2 { index( shift, &CDE ) };

# print the constants value after sub some has beenn compiled
# results in $VAR1 = *bc;
print Dumper( ABC );
print Dumper( CDE );
[download]

We don't use index a lot, but would be nice to see this fixed. Cheers, Stefan Riss