20 lines
631 B
Racket
20 lines
631 B
Racket
#lang typed/racket
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(require typed-struct-props
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typed/rackunit)
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(struct/props foo ([f : Number]) #:transparent
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#:property prop:custom-write
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(λ (this out mode)
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(fprintf out "#<f2-instance ~a>" (foo-f this))))
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(test-not-exn "The structure's constructor and type work properly"
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(λ () (ann (foo 12) foo)))
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(test-equal? "The structure's constructor and accessor work properly"
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(ann (foo-f (foo 12)) Number)
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12)
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(test-equal? "The prop:custom-write is taken into account"
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(format "~a" (foo 1))
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"#<f2-instance 1>") |