Now the guys have explained why your code is failing, you might also consider using: 

my $shop =  m/.{8}(\d{4})/ ? $1 : '0000';

[download]

or if you have an aversion to the ternary operator 

my $shop = '0000';
$shop = $1 if $AResp =~ /.{8}(\d{4})/;

[download]

In reply to Re: checking substring for numbers by BrowserUk
in thread checking substring for numbers by dwatson06

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