Including an external file in racket

2019-01-19 11:24发布

问题:

I would like to include all the functions defined in a given racket file so that I get the same effect as if they were copied. Is it possible to do that?

回答1:

You can use include as follows:

Create a file called "foo.rkt" that looks like this:

(define x 1)
(define y 2)

Then in another file:

#lang racket
(require racket/include)
(include "foo.rkt")
(+ x y)

You should see the result 3.

You can see the documentation for include as well.



回答2:

To export the functions out of a module, you use provide, consider a file "foo.rkt":

#lang racket
(define fortytwo 42)
(define (det a b c)
  (- (* b b) (* 4 a c)))
(provide (fortytwo det))

The file "bar.rkt" now can import definitions from "foo.rkt":

#lang racket
(require "foo.rkt")
(define (baz a b c)
  (+ (det a b c) (- c 4)))

The other way you could allow other files to have access to everything that’s defined in the file, is using (all-defined-out):

#lang racket
(define fortytwo 42)
(define (det a b c)
  (- (* b b) (* 4 a c)))
(provide (all-defined-out))

Hope that helps.



回答3:

You could use load

(load "assert.scm")