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Re: Some comments relating to ICFP contest

This page is part of the web mail archives of SRFI 77 from before July 7th, 2015. The new archives for SRFI 77 contain all messages, not just those from before July 7th, 2015.

On Wed, 26 Jul 2006, Michael Sperber wrote:

For sure, SRFI 77 doesn't have 32-bit or 64-bit integers *as types*.
(And that would cause major pain with the way Scheme's arithmetic is
generally set up.)

However, it does have the necessary operations to
easily implement 32-bit or 64-bit unsigned or two's complement
arithmetic in the form of `div+mod' and `div0+mod0' operations.  As
such, it also has bit operations on them.

Conceded. But the context of my comment was efficiency. How likely is it that implementations will compile the expression (exact-and (* x y) #xFFFFFFFF) to the single machine instruction available on many architectures?

Given that SRFI-74 already mentions ranges u32, s32, ..., operations such as exact-u32*, exact-s32-div, ..., would seem natural and could address the efficiency concern.

SRFI 77 doesn't have, but R6RS will have, support for "unboxed arrays"
of numbers in the form of a variation on SRFI 74.  I'm not sure they
qualify as "uniform," but is the uniformity crucial to your

Oh, they would probably do the job.