As you have + inside your character class, it will not be replaced.

my $s = 'abc123+';
$s =~ s/[^0-9+]//g;

[download]

Maybe you wanted a quantifier, which should be placed directly after the character class.

$s =~ s/[^0-9]+//g;

[download]

You can also use tr///:

$s = 'abc123+';
# remove any non-digit
$s =~ tr/0-9//cd;
# or remove any non-alphanumeric
$s =~ tr/A-Za-z0-9//cd;

[download]

See perldoc perlop for details (Search for 'tr/SEARCHLIST/REPLACEMENTLIST/cds' ).

Update

  1. removed /s from tr/// code; thanks jwkrahn

In reply to Re: stripping everything but numbers and letters by linuxer
in thread stripping everything but numbers and letters by Anonymous Monk

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