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.
28 lines
775 B
Racket
28 lines
775 B
Racket
#lang racket/base
|
|
(require racket/contract)
|
|
(require (only-in racket/list empty?))
|
|
(require (only-in racket/format ~a))
|
|
|
|
(provide (all-defined-out))
|
|
|
|
;; general way of coercing to string
|
|
(define/contract (as-string x)
|
|
(any/c . -> . string?)
|
|
(cond
|
|
[(empty? x) ""]
|
|
[(symbol? x) (symbol->string x)]
|
|
[(number? x) (number->string x)]
|
|
[(path? x) (path->string x)]
|
|
[(char? x) (~a x)]
|
|
[else (error (format "Can't make ~a into string" x))]))
|
|
|
|
|
|
(module+ test
|
|
(require rackunit)
|
|
(check-equal? (as-string '()) "")
|
|
(check-equal? (as-string 'foo) "foo")
|
|
(check-equal? (as-string 123) "123")
|
|
(define file-name-as-text "foo.txt")
|
|
(check-equal? (as-string (string->path file-name-as-text)) file-name-as-text)
|
|
(check-equal? (as-string #\¶) "¶")
|
|
) |