? could be a prefix for booleans in contrast with predicates: (define ?red-x (red? x)) ... (if (red? x) 'a 'b) ... (if ?red-x 'a 'b)
-- Vladimir
? could be a prefix for booleans in contrast with predicates: (define ?red-x (red? x)) ... (if (red? x) 'a 'b) ... (if ?red-x 'a 'b)
-- Vladimir