Yeah, Common Lisp, Racket and Smalltalk all are dynamically-typed languages that offer these sorts of features. Racket can solve this through its powerful read

Yeah, Common Lisp, Racket and Smalltalk all are dynamically-typed languages that offer these sorts of features. Racket can solve this through its powerful reader/macroexpander. The others do it by having you develop inside your run-time environment where you can take advantage of all sorts of interesting information only available at run-time.