Your average specifically checks if no arguments are provided, but doesn't actually handle that situation. Fixed: 

sub average {
    if (@_) {
        my $sum;
        for (@_) {
            $sum += $_;
        }
        return $sum/@_;
    } else {
        return undef;
    }
}

[download]

Same, but shorter: 

sub sum { my $sum; $sum += $_ for @_; $sum }
sub avg { @_ ? sum(@_)/@_ : undef }

[download]

In reply to Re^2: resetting a foreach loop! by ikegami
in thread resetting a foreach loop! by lunette

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