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Source for wiki CyclicListsCowan version 2

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cowan

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198.185.18.207

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CyclicListsCowan

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== Circular lists ==

I support CyclesMedernach with the following changes:

Remove the words "newly allocated".  Since cycles are immutable, there should be no way to tell if they share structure or not.

Clarify in `cycle-rotate` that ''k'' can be positive to rotate forwards (relative to the list passed to `make-cycle`) and negative to rotate backwards.

Add `cycle`, `cycle-ref`, `cycle-for-each`, and `cycle-fold` by analogy with R5RS `list`, `list-ref`, `for-each`, and SRFI 1 `list-fold`.  (I believe that in WG2 we should always have a fold procedure for container data structures.)

Add `cycle=?` which checks that the contents of the cycles are the same (in the sense of `eqv?`) without regard to the current position of the cycle.

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2010-10-12 00:26:56