More for R4RS

[Pavel.pa@Xerox.COM]

A little while ago, Jon asked for any other subjects to be included in R4RS.
Jon, did you mention Will's proposal to make the empty list (optionally) true?

Also, as a new proposal, I'd like to see the functions
	CHAR?, INTEGER->CHAR, and CHAR->INTEGER
renamed to
	CHARACTER?, INTEGER->CHARACTER, and CHARACTER->INTEGER.

The reason has to do with the contrast between predicate names like BOOLEAN?,
INTEGER?, and RATIONAL? (as opposed to BOOL?, INT?, and RAT?) and the name
CHAR?.

I had a bit of trouble recently trying to find a predicate for character-ness
because I naturally wanted to use the full name of the type, consistently with
the rest of Scheme.  I was mildly disgusted when I discovered that the name was
actually the abbreviation, not the full name.

I don't suggest changing the names of the other character operations because
they don't seem to be naming the type itself as explicitly.  I know this sounds
fuzzy, but it seems alright to me to have the names CHARACTER->INTEGER and
CHAR-NUMERIC? side-by-side.

Comments?

	Pavel