17 lines
517 B
Scheme
17 lines
517 B
Scheme
; 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 procedures for specific types (for lists, actually)
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;;; list-set! sublist list-fill!
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;; unspecified return value as usual
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(define (list-set! xs k x)
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(set-car! (drop xs k) x))
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(define (sublist xs start end)
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(take (drop xs start) (- end start)))
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;; unspecified return value -- no [start end] for now
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(define (list-fill! xs x)
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(pair-for-each (lambda (p) (set-car! p x)) xs))
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