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comparison lisp/tl/tl-seq.el @ 4:b82b59fe008d r19-15b3

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Import from CVS: tag r19-15b3
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date Mon, 13 Aug 2007 08:46:56 +0200
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3:30df88044ec6 4:b82b59fe008d
1 ;;; tl-seq.el --- sequence functions
2
3 ;; Copyright (C) 1995,1996 Free Software Foundation, Inc.
4
5 ;; Author: MORIOKA Tomohiko <morioka@jaist.ac.jp>
6 ;; Version:
7 ;; $Id: tl-seq.el,v 1.1.1.1 1996/12/18 03:55:31 steve Exp $
8 ;; Keywords: sequence
9
10 ;; This file is part of tl (Tiny Library).
11
12 ;; This program is free software; you can redistribute it and/or
13 ;; modify it under the terms of the GNU General Public License as
14 ;; published by the Free Software Foundation; either version 2, or (at
15 ;; your option) any later version.
16
17 ;; This program is distributed in the hope that it will be useful, but
18 ;; WITHOUT ANY WARRANTY; without even the implied warranty of
19 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
20 ;; General Public License for more details.
21
22 ;; You should have received a copy of the GNU General Public License
23 ;; along with This program; see the file COPYING. If not, write to
24 ;; the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
25 ;; Boston, MA 02111-1307, USA.
26
27 ;;; Code:
28
29 (require 'file-detect)
30
31 (cond ((file-installed-p "cl-seq.elc")
32 (require 'cl)
33 )
34 (t
35 (defun find-if (pred seq)
36 "Return the first element of sequence SEQ satisfying PRED.
37 \[tl-seq.el]"
38 (let ((i 0)(len (length seq)) element)
39 (catch 'tag
40 (while (< i len)
41 (if (funcall pred (setq element (elt seq i)))
42 (throw 'tag element)
43 )
44 (setq i (+ i 1))
45 ))
46 ))
47
48 (defun find (item seq)
49 "Return the first element which is found in sequence SEQ as item.
50 \[tl-seq.el]"
51 (find-if (function
52 (lambda (elt)
53 (eq elt item)
54 ))
55 seq))
56 ))
57
58 (defun foldr (func a seq)
59 "Return (func (func (func (... (func a Sn) ...) S2) S1) S0)
60 when func's argument is 2 and seq is a sequence whose
61 elements = S0 S1 S2 ... Sn. [tl-seq.el]"
62 (let ((i (length seq)))
63 (while (> i 0)
64 (setq i (1- i))
65 (setq a (funcall func a (elt seq i)))
66 )
67 a))
68
69 (defun foldl (func a seq)
70 "Return (... (func (func (func a S0) S1) S2) ...)
71 when func's argument is 2 and seq is a sequence whose
72 elements = S0 S1 S2 .... [tl-seq.el]"
73 (let ((len (length seq))
74 (i 0))
75 (while (< i len)
76 (setq a (funcall func a (elt seq i)))
77 (setq i (1+ i))
78 )
79 a))
80
81 (defun pack-sequence (seq size)
82 (let ((len (length seq)) (p 0) obj
83 unit (i 0)
84 dest)
85 (while (< p len)
86 (setq obj (elt seq p))
87 (setq unit (cons obj unit))
88 (setq i (1+ i))
89 (if (= i size)
90 (progn
91 (setq dest (cons (reverse unit) dest))
92 (setq unit nil)
93 (setq i 0)
94 ))
95 (setq p (1+ p))
96 )
97 (if unit
98 (setq dest (cons (reverse unit) dest))
99 )
100 (reverse dest)
101 ))
102
103
104 ;;; @ end
105 ;;;
106
107 (provide 'tl-seq)
108
109 ;;; tl-seq.el ends here