Re: [q-lang-users] Q 7.2 RC 1 issue 1: Nomenclature

[John C. <co...@cc...>]

Albert Graef scripsit:

> So we'll have to change the name of the semantic predicates then. Any 
> suggestions? How about intp, rationalp, realp, complexp? Looks familiar 
> to Lisp programmers, non-Lispers will surely hate it, but it is short 
> and at least reminiscent of the Scheme functions.

These are the representational predicates in Lisp rather than the
number-theoretic ones, though they can mostly do the work of both because
Lisp aggressively reduces complex representations to real and rational
representations to integer when possible.

I have two suggestions, neither of which I am wild about.  One is is
"isintval", "isratval", etc.  This is verbose but clear: it's about
values, not representations.  The other is cleverer and can't be confused
with the existing predicates, but may be *too* clever:  "isinZ", "isinQ",
"isinR", "isinC".

That reminds me that the rules for isintnum, isratnum, and isrealnum when
applied to type Complex do not check that the imaginary form is an *exact*
0.  As I pointed out before, an inexact 0 is really a representation for
any number n such that -d < n < d, where d is the smallest positive float.

-- 
Samuel Johnson on playing the violin:           John Cowan
"Difficult do you call it, Sir?                 co...@cc...
 I wish it were impossible."                    http://www.ccil.org/~cowan