22 lines
456 B
Racket
22 lines
456 B
Racket
#lang s-exp "kernel.rkt"
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(provide true false false?
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boolean=?
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symbol=?)
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(define true #t)
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(define false #f)
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(define (false? v) (eq? v #f))
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(define (boolean=? x y)
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(unless (and (boolean? x) (boolean? y))
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(raise-type-error 'boolean=? "boolean" (if (boolean? x) 1 0) x y))
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(eq? x y))
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(define (symbol=? x y)
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(unless (and (symbol? x) (symbol? y))
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(raise-type-error 'symbol=? "symbol" (if (symbol? x) 1 0) x y))
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(eq? x y))
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