9df037b0f6
Prevent the static contract optimizer from changing constructors under `or/sc`. i.e., for static contracts of the form `(or/sc other-scs ...)`, the optimizer cannot optimize any of the `other-scs ...` to `any/sc` but it can optimize sub-contracts of the `other-scs ...` Example: `(or/sc set?/sc (box/sc set?/sc))` in a trusted position now optimizes to itself, instead of `any/sc` Optimization can resume under a sub-contract that represents a "heavy" type constructor. (I mean, `U` is a type constructor but it's not "heavy" like that.)
23 lines
399 B
Racket
23 lines
399 B
Racket
#lang typed/racket/base
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(module u racket/base
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(define (f b)
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(set-box! b "hello"))
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(provide f))
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(define-type Maybe-Box (U #f (Boxof Integer)))
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(require/typed 'u (f (-> Maybe-Box Void)))
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(define b : Maybe-Box (box 4))
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(module+ test
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(require typed/rackunit)
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(check-exn exn:fail:contract?
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(λ () (f b)))
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(check-equal?
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(if (box? b) (+ 1 (unbox b)) (error 'deadcode))
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5))
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