Aubrey Jaffer scripsit: > | > That's reasonable: in fact, SCM doesn't support exact/exact > | > complex numbers either, which is perfectly fine. It just means > | > that no general complex number can be real. > > All real numbers are complex numbers. This derives from their > mathematical definitions.
*General* complex number is a term defined in R5RS: it means non-real complex number, where "general" is used in the sense of "general case." Because it seems to confuse people, I have removed it from the draft R7RS. > Shouldn't the predicates REAL? and COMPLEX? implement the mathematical > semantics for which they are named? Inexact numbers don't obey mathematical semantics in any case: for example, inexact addition is not associative. There are two reasonable sets of semantics here, and by providing two sets of procedures we can support both. By adding an "exact-complex" feature, a program that depends on exact complex numbers can rely on being run only on an implementation that supports them. -- Almost all theorems are true, John Cowan <[email protected]> but almost all proofs have bugs. http://www.ccil.org/~cowan --Paul Pedersen _______________________________________________ Scheme-reports mailing list [email protected] http://lists.scheme-reports.org/cgi-bin/mailman/listinfo/scheme-reports
