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23 lines
461 B
Racket
23 lines
461 B
Racket
3 years ago
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#lang racket/base
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(require racket/contract/base)
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(provide
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(struct-out terminal-symbol)
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(struct-out nonterminal-symbol)
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(contract-out
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[grammar-symbol? predicate/c]))
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;@----------------------------------------------------------------------------------------------------
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(define (grammar-symbol? v)
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(or (terminal-symbol? v) (nonterminal-symbol? v)))
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(struct terminal-symbol (value) #:transparent)
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(struct nonterminal-symbol (value) #:transparent)
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