17 lines
447 B
Racket
17 lines
447 B
Racket
#lang dotlambda/unhygienic type-expander/lang
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(require (for-syntax (lib "phc-graph/main-draft.hl.rkt")))
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(define-syntax low-graph low-graph-impl)
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(low-graph
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g
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#:∀ (A)
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(node City [streets : (Listof Street)])
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(node Street [name : String] [a : A])
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(mapping (make-city [names : (Listof (Pairof String A))])
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: City
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(City (map make-street names)))
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(mapping (make-street [p : (Pairof String A)])
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: Street
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(Street (car p) (cdr p)))) |