On Wednesday 31 December 2003 03:51 pm, Richard Kelsey wrote:
> Are there any implementations of Scheme in use where SCHEME_FALSE,
> SCHEME_TRUE, SCHEME_NULL, or SCHEME_UNSPECIFIC should be freshly
> allocated?  Or where EQ? and == are not equivalent?  (These are not
> rhetorical questions; I really would like to know -- is this an
> existing or only potential problem for portability?)

This is not exhaustive, but a quick look at a few Schemes on my disk reveals
that quite a few Schemes do use "constant objects":
	Kawa  [boolean? is a test for instance of Boolean class]
	Stklos
	SXM
	TinyScheme
	Gauche

Cheers,
-KenD