Bind the string to the operation using =~ (see perlop): 
$blah2 =~ s/\w+//;

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Update: Note this doesn't prevent you from doing this: 

my ($word) = $string =~ /(\W+)/;

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But you should be careful about maintainability. This trick appears to only work with the m// construct in list context.

In reply to Re: Quick Regex question by swiftone
in thread Quick Regex question by damian1301

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