While if( $_file_name !~ /^(\s*)$/ ) { does handle the case of undef, it will cause a warning: 
use warnings;

my $_file_name = undef;

if ($_file_name !~ /^(\s*)$/ ) {
    print "ok\n";
}

__END__

Use of uninitialized value in pattern match (m//) at test.pl line 6.

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gav^

In reply to Re: Re: Re: strict isn't everything by gav^
in thread strict isn't everything by Ovid

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