Import guile-1.8 as multiple upstream tarball component

[lilypond.git] / guile18 / ice-9 / list.scm

diff --git a/guile18/ice-9/list.scm b/guile18/ice-9/list.scm
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+;;;; List functions not provided in R5RS or srfi-1
+
+;;; Copyright (C) 2003, 2006 Free Software Foundation, Inc.
+;;;
+;; This library is free software; you can redistribute it and/or
+;; modify it under the terms of the GNU Lesser General Public
+;; License as published by the Free Software Foundation; either
+;; version 2.1 of the License, or (at your option) any later version.
+;; 
+;; This library 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
+;; Lesser General Public License for more details.
+;; 
+;; You should have received a copy of the GNU Lesser General Public
+;; License along with this library; if not, write to the Free Software
+;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+
+(define-module (ice-9 list)
+  :export (rassoc rassv rassq))
+
+(define (generic-rassoc key alist =)
+  (let loop ((ls alist))
+      (and (not (null? ls))
+          (if (= key (cdar ls))
+              (car ls)
+              (loop (cdr ls))))))
+
+(define (rassoc key alist . =)
+  (generic-rassoc key alist (if (null? =) equal? (car =))))
+
+(define (rassv key alist)
+  (generic-rassoc key alist eqv?))
+
+(define (rassq key alist)
+  (generic-rassoc key alist eq?))