15 lines
375 B
Scheme
15 lines
375 B
Scheme
#lang scheme
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(require scheme/unit
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mred/mred-sig
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"graphics-sig.ss"
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"graphics-posn-less-unit.ss")
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(provide graphics@)
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(define-unit posn@ (import) (export graphics:posn^)
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(define-struct posn (x y) #:mutable))
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(define-compound-unit/infer graphics@
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(import mred^)
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(export graphics:posn^ graphics:posn-less^)
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(link posn@ graphics-posn-less@))
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