Simplified return value and shortened code by avoiding needless use of $_: 

sub balanced {
    (my $s = shift) =~ s/[^()]//g;
    eval "qw($s); 1"
}

[download]

Or in 5.14+: 

sub balanced {
    my $s = shift =~ s/[^()]//rg;
    eval "qw($s); 1"
}

[download]

In reply to Re^3: Using qw to check for balanced parentheses (oops) by ikegami
in thread Using qw to check for balanced parentheses by unix_hacker_beard

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