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Re: predicate->char-set considered harmful

This page is part of the web mail archives of SRFI 13 from before July 7th, 2015. The new archives for SRFI 13 contain all messages, not just those from before July 7th, 2015.

Brad Lucier wrote:
> My unstated (definitely understated) point is that predicate->bitset
> will never return in the general case, which isn't much different from
> how long it will take predicate->char-set to return on systems that use
> a four-byte character representation.

A simple benchmark suggests that, on current 64-bit hardware, with
a 32-bit character code and a simple predicate that few characters
satisfy, PREDICATE->CHAR-SET would return in about an hour...

...but it would run in constant time!