I tried to run this, but it didn't do anything (the string was unmodified). A quick read later, and I came up with this...

use Regexp::Common 'pattern';

pattern name   => ['squish'],
        create => '.',
        subs   => sub { $_[1] =~ s/\W+//g; };

my $name = "Rob J Anderson";
my $squished_name = $RE{squish}->subs($name);

print "name          :$name\n";
print "squished name :$squished_name\n";


__OUTPUT__
name          :Rob J Anderson
squished name :RobJAnderson
[download]

Which fulfils all my requirements. I'm not sure about the 'create' parameter though. It seemed mandatory, but I can't see that it gets used in this context.

Anyway, thanks for all the responses.