You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
46 lines
1.8 KiB
Racket
46 lines
1.8 KiB
Racket
#lang racket/base
|
|
(provide format-datum format-datums datum?)
|
|
|
|
(define (blank? str)
|
|
(for/and ([c (in-string str)])
|
|
(char-blank? c)))
|
|
|
|
;; read "foo bar" the same way as "(foo bar)"
|
|
;; otherwise "bar" is dropped, which is too astonishing
|
|
(define (string->datum str)
|
|
(unless (blank? str)
|
|
(let ([result (read (open-input-string (format "(~a)" str)))])
|
|
(if (= (length result) 1)
|
|
(car result)
|
|
result))))
|
|
|
|
(define (datum? x) (or (list? x) (symbol? x)))
|
|
|
|
(define (format-datum datum-template . args)
|
|
(unless (datum? datum-template)
|
|
(raise-argument-error 'format-datums "datum?" datum-template))
|
|
(string->datum (apply format (format "~a" datum-template)
|
|
(map (λ (arg) (if (syntax? arg)
|
|
(syntax->datum arg)
|
|
arg)) args))))
|
|
|
|
(define (format-datums datum-template . argss)
|
|
(unless (datum? datum-template)
|
|
(raise-argument-error 'format-datums "datum?" datum-template))
|
|
(apply map (λ args (apply format-datum datum-template args)) argss))
|
|
|
|
(module+ test
|
|
(require rackunit syntax/datum)
|
|
(check-equal? (string->datum "foo") 'foo)
|
|
(check-equal? (string->datum "(foo bar)") '(foo bar))
|
|
(check-equal? (string->datum "foo bar") '(foo bar))
|
|
(check-equal? (string->datum "42") 42)
|
|
(check-equal? (format-datum '(~a-bar-~a) "foo" "zam") '(foo-bar-zam))
|
|
(check-equal? (format-datum '(~a-bar-~a) #'foo #'zam) '(foo-bar-zam))
|
|
(check-equal? (format-datum (datum (~a-bar-~a)) "foo" "zam") '(foo-bar-zam))
|
|
(check-equal? (format-datum '~a "foo") 'foo)
|
|
(check-equal? (format-datum '~a "foo") 'foo)
|
|
(check-equal? (format-datum '~a "") (void))
|
|
(check-equal? (format-datum '~a " ") (void))
|
|
(check-equal? (format-datums '(put ~a) '("foo" "zam")) '((put foo) (put zam))))
|