Re^2: 99 Problems in Perl6 (Lisp, Prolog, Haskell)

Here's a prettier way to write the Perl 6 solution:

sub group (*@array is copy) {
    gather {
        while @array {
            take [
                gather {
                    my $h = shift @array;
                    take $h;
                    while @array and $h eq @array[0] {
                        take shift @array;
                    }
                }
            ];
        }
    }
}
[download]

It would be slightly prettier if take could harvest a value en passant.

Comment on Re^2: 99 Problems in Perl6 (Lisp, Prolog, Haskell) Download Code

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Re^3: 99 Problems in Perl6 (Lisp, Prolog, Haskell) by Ovid (Cardinal) on Dec 15, 2006 at 23:12 UTC
Sweet! Why do you flatten the array? I played with that in Pugs and the asterisk seems superfluous. It seems like one is copy the elements and the other is copying the array. I thought that maybe your version would avoid aliasing problems, but even in checking that, I'm not seeing it happening. `sub group (@array is copy) { # didn't flatten gather { while @array { take [ gather { my $h = shift @array; take $h; while @array and $h eq @array[0] { take shift @array; } } ]; } } }` [download] Cheers, Ovid New address of my CGI Course.	[reply] [d/l]
Re^4: 99 Problems in Perl6 (Lisp, Prolog, Haskell) by TimToady (Parson) on Dec 15, 2006 at 23:39 UTC
I just chose to write it as a list operator so that you could say `@result = group 1,2,2,2,3,3,4,4,4,4,5,5,6,6;` [download] instead of doing it all with "scalar" arrays: `@result := group [1,2,2,2,3,3,4,4,4,4,5,5,6,6];` [download] But either approach is fine.	[reply] [d/l] [select]