After many hours of trying to trace down an anomoly in some test code, I ran into what appears to be a bug in regex caputring.

In perlre it states "The numbered variables ($1, $2, $3, etc.) and the related punctuation set ($+, $&, $`, $', and $^N) are all dynamically scoped until the end of the enclosing block or until the next successful match, whichever comes first. "

I've always taken this to mean they are "local" scoped to a block just as if you has said local($1), apparently this is not the case. Or at least not the case on my build of Perl v5.6.1

In the example below, after the first match, $1 and $2 are still populated every iteration after. Shouldn't they be reset? 
#!/usr/bin/perl
# 5.6.1
use strict;
use warnings;
use vars qw ($test);
my @values = qw ( one  var.1 test);

print join ("\t->\t",getsymbolval(@values) ),"\n";    

#################################################
sub getsymbolval{
    no strict qw (refs);
    my @syms = @_;
    foreach my $symbol (@syms){
        local $test;
        ##############################
        # Bug?                          #
        ##############################
        $symbol=~m/(\w+)\.(\d+)/;    # Shouldn't $1,$2... get reset ea
+ch time through?
        print "symbol: $symbol\t\$1: $1\t\$2:$2\n";
        print "test is ",$test++,"\n";    # Never incremented more tha
+n once
        my ($ts,$te) = ($1,$2);
    }
    wantarray ? @syms : $syms[0];    
}

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-Lee

"To be civilized is to deny one's nature."

In reply to Regex Capturing: Is this a bug or a feature? by shotgunefx

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