Skip to content

@jlongster /gist:1712455
Created

Embed URL

HTTPS clone URL

Subversion checkout URL

You can clone with
or
.
Download ZIP
traditional lisp macros
;; outlet code for implementing traditional macro expansion
;; macros
(define (expand form)
(cond
((variable? form) form)
((literal? form) form)
((macro? (car form))
(expand ((macro-function (car form)) form)))
((eq? (car form) 'quote)
form)
((eq? (car form) 'lambda)
`(lambda ,(car (cdr form))
,@(map expand (cdr (cdr form)))))
(else (map expand form))))
(define _macros_ {})
(define (macro-function name)
(ref _macros_ (symbol->string name)))
(define (install-macro name func)
(put! _macros_ (symbol->string name) func))
(define (macro? name)
(not (eq? (ref _macros_ (symbol->string name))
undefined)))
;; compiler
(define (read src)
(vector-to-list
(reader grammar src '[begin])))
(install-macro 'define (lambda (form)
`(define* ,(car (cdr form))
,@(cdr (cdr form)))))
(let ((src (fs.readFileSync "example.ol" "utf-8")))
(pretty (expand (read src))))
;; (define (foo x y z)
;; (+ x y z))
;;
;; expand to:
;;
;; (define* (foo x y z)
;; (+ x y z))
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Something went wrong with that request. Please try again.