I was surprised by the lack of such a function in List::MoreUtils recently. There is natatime, but it returns an iterator rather than using a callback.

I wonder how much speed you'd gain by replacing $f->($a,$b) with &$f. Another advanced feature for the collection!

It would be a nice bonus if you $a and $b were aliases to the args like with map. 

sub map_pairs(&@) {
    my $cb = shift;

    my $caller = caller();

    my $ap = do { no strict 'refs'; \*{$caller.'::a'} };
    my $bp = do { no strict 'refs'; \*{$caller.'::b'} };

    local *$ap;
    local *$bp;

    my @res;
    while (@_) {
        *$ap = \shift;
        *$bp = \shift;
        push @res, &$cb;
    }
    return @res;
}

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In reply to Re^2: Mini-Tutorial: Working with Odd/Even Elements by ikegami
in thread Mini-Tutorial: Working with Odd/Even Elements by ikegami

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