This was inspired by Lisp-In-Perl and my slight disappointment in both it and perl-lisp on CPAN. I've come up with my own implementation of Lisp-like linked-lists and functions/methods, so I could do what neither of the other lisps could, namely:

(defun transpose (x) (apply 'mapcar (cons 'list x))

Which on this input:
(transpose '((1 2 3) (4 5 6) (7 8 9) (10 11 12)))
Should product this output:
((1 4 7 10) (2 5 8 11) (3 6 9 12))
[download]

The perl version of this (which currently works!) goes like this:

use LISP qw(cons);

# Create linked list (Not an array!)
my $list = LISP->new([[1,2,3,4],[5,6,7,8],[9,10,11,12]]);
print $list->string; # Prints ((1 2 3 4) (5 6 7 8) (9 10 11 12))
my $mapcarf = LISP->new(\&LISP::Lambda::mapcar);
my $listf   = LISP->new($list->can('list'));
# We probably ought to go for closure on mapcarf and listf
# But this is OK for now
my $transpose = sub {$mapcarf->apply(cons($listf, shift))};
$list=$transpose->($list);
print $list->string;   # Prints ((1 5 9) (2 6 10) (3 7 11) (4 8 12))
$list=$transpose->($list);
print $list->string;   # Prints ((1 2 3 4) (5 6 7 8) (9 10 11 12))
[download]

It's only a matter of time before I get a full-blown lisp2perl compiler (I think). I'm looking for input on what I've got so far. Shall I post the whole thing(about 600 lines) or just upload it to CPAN?

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