beautiful-racket/beautiful-racket-lib/br/verbose-app.rkt
Matthew Butterick f30922a7dc add verbose-app
2016-09-02 11:42:38 -07:00

11 lines
358 B
Racket

#lang br
(require (prefix-in br: (only-in br #%app)))
(provide #%app)
(define-macro (#%app APP ARG ...)
#'(let ()
(br:#%app displayln (br:#%app format "handling subexpressions in ~a" '(APP ARG ...)))
(define result (br:#%app APP ARG ...))
(br:#%app displayln (br:#%app format "evaluating ~a = ~a" '(APP ARG ...) result ))
result))