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Perl::Critic::Policy::Bangs::ProhibitNumberedNames - Prohibit variables and subroutines with names that end in digits.


This Policy is part of the Perl::Critic::Bangs distribution.


Similar variables should be meaningfully different. A lazy way to differentiate similar variables is by tacking a number at the end.

    my $total = $price * $quantity;
    my $total2 = $total + ($total * $taxrate);
    my $total3 = $total2 + $shipping;

The difference between $total and $total3 is not described by the silly "3" at the end. Instead, it should be:

    my $merch_total = $price * $quantity;
    my $subtotal = $merch_total + ($merch_total * $taxrate);
    my $grand_total = $subtotal + $shipping;

Both variable and subroutine names are checked.

See for more of my ranting on this.


This policy has two options: exceptions and add_exceptions.


This policy starts with a list of numbered names that are legitimate to have ending with a number:

    base64 md5 rc4 sha0 sha1 sha256 utf8 x11 win32

The exceptions for the policy also apply to names based on the exceptions. If $base64 is acceptable as an exception, so is $calculated_base64. The exception must be separated from the left part of the name by at least one underscore to be recognized.

The exceptions are case-insensitive. $UTF8 and $utf8 are both seen the same as far as being exceptions.

To replace the list of exceptions, specify a value for the exceptions option.

    exceptions = logan7 babylon5


To add exceptions to the list, give a value for add_exceptions in your .perlcriticrc file like this:

    add_exceptions = adam12 route66


Andy Lester <andy at>


Copyright (c) 2006-2013 Andy Lester

This library is free software; you can redistribute it and/or modify it under the terms of the Artistic License 2.0.