But it would be nice if you could make it O(1) anyway without linked lists.
You could implement cdr as returning a shared hash slice. With some XS hacking you can probably make it work for some cases. Though you may have to make arrays immutable to do it right :-)

update: it seems to me you could implement this in pure perl using tied arrays. But it would get more inefficient for each slice-of-a-slice-of-a-slice.

"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re^3: No Iterators Allowed by Joost
in thread No Iterators Allowed by runrig

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