I don't care about "cool". I care about "useful". Callbacks are fundamentally inflexible (Re: Are you looking at XML processing the right way? (merge)).

Note that turning my iterator into your callback interface is trivial: 

sub forDerange(&@)
{
    my $cv= shift @_;
    my $iter= genDerange( @_ );
    my @list;
    while(  @list= $iter->()  ) {
        $cv->( @list );
    }
}

[download]

Try to go the other way. (:

- tye        

In reply to Re^2: Derangements iterator (callbacks) by tye
in thread Derangements iterator by tye

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