home *** CD-ROM | disk | FTP | other *** search
- ;;"comlist.scm" Implementation of COMMON LISP list functions for Scheme
- ; Copyright (C) 1991, 1993, 1995 Aubrey Jaffer.
- ;
- ;Permission to copy this software, to redistribute it, and to use it
- ;for any purpose is granted, subject to the following restrictions and
- ;understandings.
- ;
- ;1. Any copy made of this software must include this copyright notice
- ;in full.
- ;
- ;2. I have made no warrantee or representation that the operation of
- ;this software will be error-free, and I am under no obligation to
- ;provide any services, by way of maintenance, update, or otherwise.
- ;
- ;3. In conjunction with products arising from the use of this
- ;material, there shall be no use of my name in any advertising,
- ;promotional, or sales literature without prior written consent in
- ;each case.
-
- ;;; Some of these functions may be already defined in your Scheme.
- ;;; Comment out those definitions for functions which are already defined.
-
- ;;;; LIST FUNCTIONS FROM COMMON LISP
-
- ;;;From: hugh@ear.mit.edu (Hugh Secker-Walker)
- (define (comlist:make-list k . init)
- (set! init (if (pair? init) (car init)))
- (do ((k k (+ -1 k))
- (result '() (cons init result)))
- ((<= k 0) result)))
-
- (define (comlist:copy-list lst) (append lst '()))
-
- (define (comlist:adjoin e l) (if (memv e l) l (cons e l)))
-
- (define (comlist:union l1 l2)
- (cond ((null? l1) l2)
- ((null? l2) l1)
- (else (comlist:union (cdr l1) (comlist:adjoin (car l1) l2)))))
-
- (define (comlist:intersection l1 l2)
- (cond ((null? l1) l1)
- ((null? l2) l2)
- ((memv (car l1) l2) (cons (car l1) (comlist:intersection (cdr l1) l2)))
- (else (comlist:intersection (cdr l1) l2))))
-
- (define (comlist:set-difference l1 l2)
- (cond ((null? l1) l1)
- ((memv (car l1) l2) (comlist:set-difference (cdr l1) l2))
- (else (cons (car l1) (comlist:set-difference (cdr l1) l2)))))
-
- (define (comlist:position obj lst)
- (letrec ((pos (lambda (n lst)
- (cond ((null? lst) #f)
- ((eqv? obj (car lst)) n)
- (else (pos (+ 1 n) (cdr lst)))))))
- (pos 0 lst)))
-
- (define (comlist:reduce-init p init l)
- (if (null? l)
- init
- (comlist:reduce-init p (p init (car l)) (cdr l))))
-
- (define (comlist:reduce p l)
- (cond ((null? l) l)
- ((null? (cdr l)) (car l))
- (else (comlist:reduce-init p (car l) (cdr l)))))
-
- (define (comlist:some pred l . rest)
- (cond ((null? rest)
- (let mapf ((l l))
- (and (not (null? l))
- (or (pred (car l)) (mapf (cdr l))))))
- (else (let mapf ((l l) (rest rest))
- (and (not (null? l))
- (or (apply pred (car l) (map car rest))
- (mapf (cdr l) (map cdr rest))))))))
-
- (define (comlist:every pred l . rest)
- (cond ((null? rest)
- (let mapf ((l l))
- (or (null? l)
- (and (pred (car l)) (mapf (cdr l))))))
- (else (let mapf ((l l) (rest rest))
- (or (null? l)
- (and (apply pred (car l) (map car rest))
- (mapf (cdr l) (map cdr rest))))))))
-
- (define (comlist:notany pred . ls) (not (apply comlist:some pred ls)))
-
- (define (comlist:notevery pred . ls) (not (apply comlist:every pred ls)))
-
- (define (comlist:find-if t l)
- (cond ((null? l) #f)
- ((t (car l)) (car l))
- (else (comlist:find-if t (cdr l)))))
-
- (define (comlist:member-if t l)
- (cond ((null? l) #f)
- ((t (car l)) l)
- (else (comlist:member-if t (cdr l)))))
-
- (define (comlist:remove p l)
- (cond ((null? l) l)
- ((eqv? p (car l)) (comlist:remove p (cdr l)))
- (else (cons (car l) (comlist:remove p (cdr l))))))
-
- (define (comlist:remove-if p l)
- (cond ((null? l) l)
- ((p (car l)) (comlist:remove-if p (cdr l)))
- (else (cons (car l) (comlist:remove-if p (cdr l))))))
-
- (define (comlist:remove-if-not p l)
- (cond ((null? l) l)
- ((p (car l)) (cons (car l) (comlist:remove-if-not p (cdr l))))
- (else (comlist:remove-if-not p (cdr l)))))
-
- (define comlist:nconc
- (if (provided? 'rev2-procedures) append!
- (lambda args
- (cond ((null? args) '())
- ((null? (cdr args)) (car args))
- ((null? (car args)) (apply comlist:nconc (cdr args)))
- (else
- (set-cdr! (last-pair (car args))
- (apply comlist:nconc (cdr args)))
- (car args))))))
-
- ;;;From: hugh@ear.mit.edu (Hugh Secker-Walker)
- (define (comlist:nreverse rev-it)
- ;;; Reverse order of elements of LIST by mutating cdrs.
- (cond ((null? rev-it) rev-it)
- ((not (list? rev-it))
- (slib:error "nreverse: Not a list in arg1" rev-it))
- (else (do ((reved '() rev-it)
- (rev-cdr (cdr rev-it) (cdr rev-cdr))
- (rev-it rev-it rev-cdr))
- ((begin (set-cdr! rev-it reved) (null? rev-cdr)) rev-it)))))
-
- (define (comlist:last lst n)
- (comlist:nthcdr (- (length lst) n) lst))
-
- (define (comlist:butlast lst n)
- (letrec ((l (- (length lst) n))
- (bl (lambda (lst n)
- (cond ((null? lst) lst)
- ((positive? n)
- (cons (car lst) (bl (cdr lst) (+ -1 n))))
- (else '())))))
- (bl lst (if (negative? n)
- (slib:error "negative argument to butlast" n)
- l))))
-
- (define (comlist:nthcdr n lst)
- (if (zero? n) lst (comlist:nthcdr (+ -1 n) (cdr lst))))
-
- (define (comlist:butnthcdr n lst)
- (letrec ((bn (lambda (lst n)
- (cond ((null? lst) lst)
- ((positive? n)
- (cons (car lst) (bn (cdr lst) (+ -1 n))))
- (else '())))))
- (bn lst (if (negative? n)
- (slib:error "negative argument to butnthcdr" n)
- n))))
-
- ;;;; CONDITIONALS
-
- (define (comlist:and? . args)
- (cond ((null? args) #t)
- ((car args) (apply comlist:and? (cdr args)))
- (else #f)))
-
- (define (comlist:or? . args)
- (cond ((null? args) #f)
- ((car args) #t)
- (else (apply comlist:or? (cdr args)))))
-
- ;;; Checks to see if a list has any duplicate MEMBERs.
- (define (comlist:has-duplicates? lst)
- (cond ((null? lst) #f)
- ((member (car lst) (cdr lst)) #t)
- (else (comlist:has-duplicates? (cdr lst)))))
-
- ;;; remove duplicates of MEMBERs of a list
- (define (comlist:remove-duplicates lst)
- (letrec ((rem-dup
- (lambda (lst nlst)
- (cond ((null? lst) nlst)
- ((member (car lst) nlst) (rem-dup (cdr lst) nlst))
- (else (rem-dup (cdr lst) (cons (car lst) nlst)))))))
- (rem-dup lst '())))
-
- (define (comlist:list* x . y)
- (define (list*1 x)
- (if (null? (cdr x))
- (car x)
- (cons (car x) (list*1 (cdr x)))))
- (if (null? y)
- x
- (cons x (list*1 y))))
-
- (define (comlist:atom? a)
- (not (pair? a)))
-
- (define (type-of obj)
- (cond
- ((null? obj) 'null)
- ((boolean? obj) 'boolean)
- ((char? obj) 'char)
- ((number? obj) 'number)
- ((string? obj) 'string)
- ((symbol? obj) 'symbol)
- ((input-port? obj) 'port)
- ((output-port? obj) 'port)
- ((procedure? obj) 'procedure)
- ((eof-object? obj) 'eof-object)
- ((list? obj) 'list)
- ((pair? obj) 'pair)
- ((and (provided? 'array) (array? obj)) 'array)
- ((and (provided? 'record) (record? obj)) 'record)
- ((vector? obj) 'vector)
- (else '?)))
-
- (define (coerce obj result-type)
- (define (err) (slib:error 'coerce "couldn't" obj '-> result-type))
- (define obj-type (type-of obj))
- (cond
- ((eq? obj-type result-type) obj)
- (else
- (case obj-type
- ((char) (case result-type
- ((number integer) (char->integer obj))
- ((string) (string obj))
- ((symbol) (string->symbol (string obj)))
- ((list) (list obj))
- ((vector) (vector obj))
- (else (err))))
- ((number) (case result-type
- ((char) (integer->char obj))
- ((atom) obj)
- ((integer) obj)
- ((string) (number->string obj))
- ((symbol) (string->symbol (number->string obj)))
- ((list) (string->list (number->string obj)))
- ((vector) (list->vector (string->list (number->string obj))))
- (else (err))))
- ((string) (case result-type
- ((char) (if (= 1 (string-length obj)) (string-ref obj 0)
- (err)))
- ((atom) (or (string->number obj) (string->symbol obj)))
- ((number integer) (or (string->number obj) (err)))
- ((symbol) (string->symbol obj))
- ((list) (string->list obj))
- ((vector) (list->vector (string->list obj)))
- (else (err))))
- ((symbol) (case result-type
- ((char) (coerce (symbol->string obj) 'char))
- ((number integer) (coerce (symbol->string obj) 'number))
- ((string) (symbol->string obj))
- ((atom) obj)
- ((list) (string->list (symbol->string obj)))
- ((vector) (list->vector (string->list (symbol->string obj))))
- (else (err))))
- ((list) (case result-type
- ((char) (if (and (= 1 (length obj))
- (char? (car obj)))
- (car obj)
- (err)))
- ((number integer)
- (or (string->number (list->string obj)) (err)))
- ((string) (list->string obj))
- ((symbol) (string->symbol (list->string obj)))
- ((vector) (list->vector obj))
- (else (err))))
- ((vector) (case result-type
- ((char) (if (and (= 1 (vector-length obj))
- (char? (vector-ref obj 0)))
- (vector-ref obj 0)
- (err)))
- ((number integer)
- (or (string->number (coerce obj string)) (err)))
- ((string) (list->string (vector->list obj)))
- ((symbol) (string->symbol (coerce obj string)))
- ((list) (list->vector obj))
- (else (err))))
- (else (err))))))
-
- (define (comlist:delete obj list)
- (let delete ((list list))
- (cond ((null? list) '())
- ((equal? obj (car list)) (delete (cdr list)))
- (else
- (set-cdr! list (delete (cdr list)))
- list))))
-
- (define (comlist:delete-if pred list)
- (let delete-if ((list list))
- (cond ((null? list) '())
- ((pred (car list)) (delete-if (cdr list)))
- (else
- (set-cdr! list (delete-if (cdr list)))
- list))))
-
- (define (comlist:delete-if-not pred list)
- (let delete-if ((list list))
- (cond ((null? list) '())
- ((not (pred (car list))) (delete-if (cdr list)))
- (else
- (set-cdr! list (delete-if (cdr list)))
- list))))
-
- ;;; exports
-
- (define make-list comlist:make-list)
- (define copy-list comlist:copy-list)
- (define adjoin comlist:adjoin)
- (define union comlist:union)
- (define intersection comlist:intersection)
- (define set-difference comlist:set-difference)
- (define position comlist:position)
- (define reduce-init comlist:reduce-init)
- (define reduce comlist:reduce) ; reduce is also in collect.scm
- (define some comlist:some)
- (define every comlist:every)
- (define notevery comlist:notevery)
- (define notany comlist:notany)
- (define find-if comlist:find-if)
- (define member-if comlist:member-if)
- (define remove comlist:remove)
- (define remove-if comlist:remove-if)
- (define remove-if-not comlist:remove-if-not)
- (define nconc comlist:nconc)
- (define nreverse comlist:nreverse)
- (define last comlist:last)
- (define butlast comlist:butlast)
- (define nthcdr comlist:nthcdr)
- (define butnthcdr comlist:butnthcdr)
- (define and? comlist:and?)
- (define or? comlist:or?)
- (define has-duplicates? comlist:has-duplicates?)
- (define remove-duplicates comlist:remove-duplicates)
-
- (define delete-if-not comlist:delete-if-not)
- (define delete-if comlist:delete-if)
- (define delete comlist:delete)
- (define comlist:atom comlist:atom?)
- (define atom comlist:atom?)
- (define atom? comlist:atom?)
- (define list* comlist:list*)
-