40 lines
1.0 KiB
Scheme
40 lines
1.0 KiB
Scheme
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; Copyright (c) 2003 RT Happe <rthappe at web de>
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; See the file COPYING distributed with the Scheme Untergrund Library
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;;; sequence operations definABLE in terms of the elementary operations
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;;; [ not much there yet ]
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(define (ident x) x)
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(define (sequence->list s)
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(gen-dispatch
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((string? string->list)
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(byte-vector? contiguous-sequence->list)
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(vector? vector->list)
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(list? ident)
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(behaved-sequence? contiguous-sequence->list))
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s))
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(define (sequence-fill! s x)
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(gen-dispatch
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((string? string-fill!)
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(byte-vector? contiguous-sequence-fill!)
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(vector? vector-fill!)
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(list? ident)
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(behaved-sequence? contiguous-sequence-fill!))
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s x))
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(define (subsequence s start end)
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(cond ((pair? s)
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(sublist s start end))
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((string? s)
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(substring s start end))
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(else (contiguous-subsequence s start end))))
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;; this is rather inefficient for lists-only uses, but supports mixed
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;; sequences (comparing lists against vectors, for instance)
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(define every/bounds contiguous-every/bounds)
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