NetNews Usenet Archive 1992 #27/NN_1992_27.iso/spool/comp/lang/scheme/2606

Internet Message Format | 1992-11-17 | 5.1 KB

Path: sparky!uunet!charon.amdahl.com!pacbell.com!ames!olivea!charnel!psgrain!percy!data!kend
From: [e-mail] (Ken Dickey)
Newsgroups: comp.lang.scheme
Subject: Re: Modules for Scheme
Message-ID: <[e-mail]>
Date: 16 Nov 92 19:17:35 GMT
References: <[e-mail]>
Distribution: comp
Organization: Microtek DSD, Hillsboro, OR
Lines: 164

[e-mail] (Robert Goldman) writes:


>I was considering composing a package of definitions to give a
>module facility to Scheme (Scheme does what we want with just
>lexical scoping, o' course, but I would like to augment the syntax
>to enhance readability).  I would like to take a look at any such
>packages which exist now to avoid reinventing the wheel.  Any
>pointers to such would be appreciated.

Pavel Curtis & James Rauen: "A Module System for Scheme",  Proceedings
of the 1990 ACM Conference on Lisp and Functional Programming, June
27-29, 1992, [ACM # 552900]

Sho-Huan Simun Tung: "Interactive Modular Programming in Scheme,
Proceedings of the 1992 ACM Conference on Lisp and Functional
Programming, June 22-24, 1992, [ACM # 552920].

The traditional trivial module system follows.

Enjoy!
-Ken
==============================================================
;; FILE        "country.scm"
;; IMPLEMENTS    NameSpace management via IMPORT/EXPORT
;; AUTHOR    Kenneth A Dickey
;; DATE        1991 October 26
;; LAST UPDATED    1991 November 1 -- updated EXPORT syntax

;(##declare (standard-bindings))  ;; Gambit 1.71

;; INTERFACE:
;;
;;   (IMPORT <country> <name>) -> value of <name> exported by <country>.
;;
;;   (EXPORT-LIST <country>)   -> list of exported names (symbols).
;;
;;   (EXPORT <name1> <name2> ...)  ;; returned as definition of exporting
;;                                 ;; `country'.

;; NOTES:
;;
;;   The EXPORT special form needs to be defined in your local syntax
;; system.  Note that the scheme initial environment definitions are
;; available from SCHEME::COUNTRY if this file is loaded in the
;; initial environment.  This allows files to be loaded multiple times
;; without damaging definitions (e.g. redefining LOAD each time).


;; SAMPLE USAGE: DEFINITION OF EXPORTING `COUNTRY'
;;
;@ (define BIT-MANIPULATION::COUNTRY
;@   (let ()
;@    (define (BIT-AND some-bits other-bits) ...)
;@    (define (BIT-XOR some-bits other-bits) ...)
;@    ...
;@
;@    (EXPORT bit-and bit-or ...)  ;; the return value
;@ ) )
;@ ;; EOF


;; SAMPLE USAGE: IMPORT LOADFILE
;;
;@ ;;Recognize country--add to the United Nations 8^)
;@ (require 'bit-manipulation) ;; a.k.a. (load "bits.scm")
;@ (define BIT-AND (IMPORT bit-manipulation::country 'bit-and))
;@ (define BIT-XOR (IMPORT bit-manipulation::country 'bit-xor))
;@ ...
;@ ;; EOF


;;
;; IMPLEMENTATION
;;

  (define (IMPORT country name)
     (let ( (probe (assq name country)) )
    (and probe (cdr probe))
  )  )


  (define (EXPORT-LIST country) (map car country))


  ;; Redefine EXPORT in your local syntax system
  ;; R^4RS

  (define-syntax EXPORT
    (syntax-rules ()
      ((export <name> ...)
      ;=>
      (list (cons '<name> <name>) ...))  ;; just an a-list
  ) )

;; OLD STYLE
;;  (##define-macro (EXPORT . name-list)
;;    `(list ,@(map (lambda (name) `(cons (quote ,name) ,name)) name-list)) )



;;
;; CAPTURE (presumed) INITIAL SCHEME ENVIRONMENT
;;

  (define SCHEME::COUNTRY

    (EXPORT

    ; IEEE Scheme

    not    boolean?    eqv?    eq?    equal?
    pair?    cons    car    cdr    set-car!    set-cdr!
    caar    cadr    cdar    cddr    caaar    caadr    cadar
    caddr    cdaar    cdadr    cddar    cdddr    caaaar    caaadr
    caadar    caaddr    cadaar    cadadr    caddar    cadddr    cdaaar
    cdaadr    cdadar    cdaddr    cddaar    cddadr    cdddar    cddddr
    null?    list?    list    length    append    reverse    list-ref
    memq    memv    member    assq    assv    assoc
    symbol?    symbol->string    string->symbol    number?    complex?
    real?    rational?    integer?    exact?    inexact?
    =    <    >    <=    >=    zero?    positive?
    negative?    odd?    even?    max    min
    +    *    -    /    abs    quotient
    remainder    modulo    gcd    lcm    numerator
    denominator    floor    ceiling    truncate    round
    rationalize    exp    log    sin    cos    tan
    asin    acos    atan    sqrt    expt    make-rectangular
    make-polar    real-part    imag-part    magnitude
    angle    exact->inexact    inexact->exact
    number->string    string->number
    char?    char=?    char<?    char>?    char<=?    char>=?    char-ci=?
    char-ci<?    char-ci>?    char-ci<=?    char-ci>=?
    char-alphabetic?    char-numeric?    char-whitespace?
    char-upper-case?    char-lower-case?    char->integer
    integer->char    char-upcase    char-downcase
    string?    make-string    string    string-length    string-ref
    string-set!    string=?    string<?    string>?
    string<=?    string>=?    string-ci=?    string-ci<?
    string-ci>?    string-ci<=?    string-ci>=?    substring
    string-append    vector?    make-vector    vector    vector-length
    vector-ref    vector-set!    procedure?    apply    map
    for-each    call-with-current-continuation    call-with-input-file
    call-with-output-file    input-port?    output-port?
    current-input-port    current-output-port    open-input-file
    open-output-file    close-input-port    close-output-port
    eof-object?    read    read-char    peek-char    write
    display    newline    write-char

    ; R4RS Scheme

    list-tail    string->list    list->string    string-copy
    string-fill!    vector->list    list->vector    vector-fill!
    force    with-input-from-file    with-output-to-file
    char-ready?    load    transcript-on    transcript-off

    ; Your favorate extensions here...

;@;    touch
    )
  )


;;            --- E O F ---            ;;