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Diffstat (limited to 'oop/goops/util.scm')
-rw-r--r-- | oop/goops/util.scm | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/oop/goops/util.scm b/oop/goops/util.scm new file mode 100644 index 000000000..0e6df4147 --- /dev/null +++ b/oop/goops/util.scm @@ -0,0 +1,112 @@ +;;;; Copyright (C) 1999, 2000 Free Software Foundation, Inc. +;;;; +;;;; 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, 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 software; see the file COPYING. If not, write to +;;;; the Free Software Foundation, Inc., 59 Temple Place, Suite 330, +;;;; Boston, MA 02111-1307 USA +;;;; + + +(define-module (oop goops util) + :no-backtrace + ) + +(export any every filter + mapappend find-duplicate top-level-env top-level-env? + map* for-each* length* improper->proper + ) + +;;; +;;; {Utilities} +;;; + +(define (any pred lst . rest) + (if (null? rest) ;fast path + (and (not (null? lst)) + (let loop ((head (car lst)) (tail (cdr lst))) + (if (null? tail) + (pred head) + (or (pred head) + (loop (car tail) (cdr tail)))))) + (let ((lsts (cons lst rest))) + (and (not (any null? lsts)) + (let loop ((heads (map car lsts)) (tails (map cdr lsts))) + (if (any null? tails) + (apply pred heads) + (or (apply pred heads) + (loop (map car tails) (map cdr tails))))))))) + +(define (every pred lst . rest) + (if (null? rest) ;fast path + (or (null? lst) + (let loop ((head (car lst)) (tail (cdr lst))) + (if (null? tail) + (pred head) + (and (pred head) + (loop (car tail) (cdr tail)))))) + (let ((lsts (cons lst rest))) + (or (any null? lsts) + (let loop ((heads (map car lsts)) (tails (map cdr lsts))) + (if (any null? tails) + (apply pred heads) + (and (apply pred heads) + (loop (map car tails) (map cdr tails))))))))) + +(define (filter test? list) + (cond ((null? list) '()) + ((test? (car list)) (cons (car list) (filter test? (cdr list)))) + (else (filter test? (cdr list))))) + +(define (mapappend func . args) + (if (memv '() args) + '() + (append (apply func (map car args)) + (apply mapappend func (map cdr args))))) + +(define (find-duplicate l) ; find a duplicate in a list; #f otherwise + (cond + ((null? l) #f) + ((memv (car l) (cdr l)) (car l)) + (else (find-duplicate (cdr l))))) + +(define (top-level-env) + (if *top-level-lookup-closure* + (list *top-level-lookup-closure*) + '())) + +(define (top-level-env? env) + (or (null? env) + (procedure? (car env)))) + +(define (map* fn . l) ; A map which accepts dotted lists (arg lists + (cond ; must be "isomorph" + ((null? (car l)) '()) + ((pair? (car l)) (cons (apply fn (map car l)) + (apply map* fn (map cdr l)))) + (else (apply fn l)))) + +(define (for-each* fn . l) ; A for-each which accepts dotted lists (arg lists + (cond ; must be "isomorph" + ((null? (car l)) '()) + ((pair? (car l)) (apply fn (map car l)) (apply for-each* fn (map cdr l))) + (else (apply fn l)))) + +(define (length* ls) + (do ((n 0 (+ 1 n)) + (ls ls (cdr ls))) + ((not (pair? ls)) n))) + +(define (improper->proper ls) + (if (pair? ls) + (cons (car ls) (improper->proper (cdr ls))) + (list ls))) |