/usr/share/acl2-4.3/books/str/prefix-lines.lisp is in acl2-books-source 4.3-3.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 | ; ACL2 String Library
; Copyright (C) 2009-2010 Centaur Technology
;
; Contact:
; Centaur Technology Formal Verification Group
; 7600-C N. Capital of Texas Highway, Suite 300, Austin, TX 78731, USA.
; http://www.centtech.com/
;
; This program is free software; you can redistribute it and/or modify it under
; the terms of the GNU General Public License as published by the Free Software
; Foundation; either version 2 of the License, or (at your option) any later
; version. This program is distributed in the hope that it will be useful but
; WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
; FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
; more details. You should have received a copy of the GNU General Public
; License along with this program; if not, write to the Free Software
; Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA.
;
; Original author: Jared Davis <jared@centtech.com>
(in-package "STR")
(include-book "cat")
(local (include-book "arithmetic"))
(defund prefix-lines-aux (n x xl acc prefix)
(declare (xargs :guard (and (natp n)
(stringp x)
(natp xl)
(<= n xl)
(= xl (length x))
(stringp prefix))
:measure (nfix (- (nfix xl) (nfix n)))))
(let ((n (mbe :logic (nfix n) :exec n))
(xl (mbe :logic (nfix xl) :exec xl)))
(if (mbe :logic (zp (- xl n))
:exec (= n xl))
acc
(let* ((char (char x n))
(acc (cons char acc))
(acc (if (eql char #\Newline)
(str::revappend-chars prefix acc)
acc)))
(prefix-lines-aux (+ 1 n) x xl acc prefix)))))
(defthm character-listp-of-prefix-lines-aux
(implies (and (natp n)
(stringp x)
(natp xl)
(<= n xl)
(= xl (length x))
(stringp rprefix)
(character-listp acc))
(character-listp (prefix-lines-aux n x xl acc prefix)))
:hints(("Goal"
:induct (prefix-lines-aux n x xl acc prefix)
:in-theory (enable prefix-lines-aux))))
(defund prefix-lines (x prefix)
":Doc-Section Str
Add a prefix to every line in a string~/
~c[(prefix-lines x prefix)] builds a new string by adding ~c[prefix] to the
start of every line in the string ~c[x]. The start of ~c[x] is regarded
as the start of a line, and also gets the prefix. For instance,
~bv[]
(prefix-lines \"hello world
goodbye world\" \" ** \")
~ev[]
Would create the following result:
~bv[]
\" ** hello world
** goodbye world\"
~ev[]
This is sometimes useful for indenting blobs of text when you are trying to
pretty-print things. The operation is fairly efficient: we cons everything
into a character list and then coerce it back into a string at the end.~/~/"
(declare (xargs :guard (and (stringp x)
(stringp prefix))))
(let* ((acc (str::revappend-chars prefix nil))
(rchars (prefix-lines-aux 0 x (length x) acc prefix))
(rstr (coerce rchars 'string)))
(reverse rstr)))
(defthm stringp-of-prefix-lines
(stringp (prefix-lines x prefix))
:rule-classes :type-prescription
:hints(("Goal" :in-theory (enable prefix-lines))))
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