11 lines
213 B
Racket
11 lines
213 B
Racket
#lang racket/base
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(provide once)
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(require (for-syntax racket/base))
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(define-syntax once
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(λ (stx)
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(raise-syntax-error
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'once
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"The \"once\" identifier can only be used in some contexts"
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stx))) |