Why use map without using it's return value? why not two for loops? merlyn doesn't like that, and I agree with him. 
# for loop
for my $i (0 .. $#a1) {
    for my $j (0 .. $#a2) {
        push @indices, $i
            if $a2[$j] eq $a1[$i];
    }
}

[download]
# schwartzian [sp?] transform (perhaps not a paradigmatic example thou
+gh)
my @indicies = map {$_->[0]}
    grep {$a1[$_->[0]] eq $a2[$_->[1]]}
    map { my $l = $_; (map {[$l,$_]} 0 .. $#a2) } 0 .. $#a2;

[download]

-Paul

In reply to Re: Scanning a list for indices by jettero
in thread Scanning a list for indices by cmv

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