On Wed, Jul 13, 2011 at 12:08 PM, <[email protected]> wrote: > > ;; we assume indexes are 2 bits shorter than fixnums > ;; We're generating a reference to fixnum? rather than calling it, so > ;; we're safe from fixnum size issues on different platforms. > -(define (index? x) (and (fixnum? x) (>= x 0) (fixnum? (* x 4)))) > +(define (index? x) > + (and (fixnum? x) (unsafe-fx>= x 0) (fixnum? (unsafe-fx* x 4))))
How is this possibly ok? If `x' is (/ MAX_FIXNUM 2), then this code has no semantics. -- sam th [email protected] _________________________________________________ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/dev
