Patched require/untyped-contract to accept a language spec.

[Rscho314]

Hi @bennn ,

This is a very modest proposal for #1286. I did not patch the docs yet, but I will do so if there is interest in this pull request. It seems to work with the following test code (changed language to typed/racket/no-check):

server.rkt

#lang typed/racket/no-check ;shallow ;optional ;no-check

(provide mynum check-array-shape)

(define mynum 42)

(define-type (MVec T) (Mutable-Vectorof T))

(define-type Indexes (MVec Index))
(define-type In-Indexes (U (MVec Integer) Indexes))

(: check-array-shape (In-Indexes (-> Nothing) -> Indexes))
(define (check-array-shape ds fail)
  (define dims (vector-length ds))
  (define: new-ds : Indexes (make-vector dims 0))
  (let loop ([#{i : Nonnegative-Fixnum} 0])
    (cond [(i . < . dims)
           (define di (vector-ref ds i))
           (cond [(index? di)  (vector-set! new-ds i di)
                               (loop (+ i 1))]
                 [else  (fail)])]
          [else  new-ds])))

main.rkt

#lang racket/base

(require typed/untyped-utils
         typed/racket/no-check
         (except-in "server.rkt"
                    check-array-shape))

(require/untyped-contract
 "server.rkt"
 'typed/racket/no-check
 [check-array-shape  #;((Mutable-Vectorof Integer) (-> Nothing) -> (Mutable-Vectorof Index))
                     ((Vectorof Integer) (-> Nothing) -> (Vectorof Index))])

(check-array-shape (vector 1 2 3) (lambda () (error 'die)))

Cheers!

[bennn]

Hi Raol, sorry I am so slow. Just want you to know that I know this PR exists and will take a look soon!

[bennn]

EDIT: nevermind, the problem was that I used 'typed/racket/no-check as the language spec. We should improve the message.

Tried running this on the example, and I'm getting an error about an (only-in quote):

only-in: identifier `quote' not included in nested require spec
  at: "server.rkt"
  in: (only-in "server.rkt" (quote quote3) (check-array-shape check-array-shape4))

[bennn]

This was typed/racket before. I think it needs to be the language-spec.
EDIT: oh, I misremembered the argument order. This could just be #'here.

[Rscho314]

@bennn Thanks for the feedback. I've changed the datum->syntax context to #'_. I'm not really up to good coding style conventions for Racket, so I hope I've done the right thing.

EDIT:

As for the error about an (only-in quote), I agree the message could be improved. From a cursory glance at the source, I think the most feasible way of doing it is to wrap require/untyped-contract in a with-handlers form and providing a custom message. Letting the exception bubble up to handle it more generally immediately brings us to core racket collections that I'd rather not touch. Thoughts ?

Is there anything else I can do to improve this PR ?

[bennn]

how about changing the syntax from typed/racket/shallow to #:lang typed/racket/shallow --- from :id to keyword +:expr ? that should improve the error and make this easier to use later.

[github-actions]

Resyntax analyzed 1 file in this pull request and found no issues.

[bennn]

keep the indentation like it was