Hmm, you get the results you expect if you place an extra pair of braces around the if construct. 
#!/usr/bin/perl -w
use strict;
$|++;

my $valid    ='realgoodname';
my $invalid  ='bad name';
my ($test1,$test2);
{
    if ($valid =~ /^([a-z]+)$/i){
        $test1=$1;
    }
}
{
    $invalid =~ /^([a-z]+)$/i;
    $test2=$1;
    die "Invalid test2" unless $test2;
}
print "Valid word\t= $valid\nInvalid word\t= $invalid\n\n";
print "Valid test\t= $test1\nInvalid test\t= $test2\n";

exit();

[download]
Apparently, stuff inside of the braces on an if statement is not localized. Therefore, the behaviour of $1 does not fit any of the conditions you specified from the Camel. I learn something new about Perl every day :)

Cheers,
Ovid

Update: Duh! The regex wasn't in the block. It's amazing how simple these things often turn out to be. Thanks, chromatic.

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In reply to (Ovid) Re: Localized Backreferences by Ovid
in thread Localized Backreferences, If Statements & Blocks by doran

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