;;;"scheme48.init" Initialisation for SLIB for Scheme48-0.57	-*-scheme-*-
;;; Author: Aubrey Jaffer
;;;
;;; This code is in the public domain.

,batch on
,load-package floatnums
,config
,load =scheme48/misc/packages.scm
(define-structure slib-primitives
  (export s48-getenv
	  s48-system
	  s48-current-error-port
	  s48-force-output
	  s48-with-handler
	  s48-ascii->char
	  s48-error)
  (open scheme signals ascii extended-ports i/o primitives handle
	posix c-system-function)
  (begin
    (define s48-getenv lookup-environment-variable)
    (define s48-system system)
    (define s48-current-error-port current-error-port)
    (define s48-force-output force-output)
    (define s48-with-handler with-handler)
    (define s48-ascii->char ascii->char)
    (define s48-error error)))
,user
,open slib-primitives

(define getenv s48-getenv)
(define system s48-system)

;;; (software-type) should be set to the generic operating system type.
;;; UNIX, VMS, MACOS, AMIGA and MS-DOS are supported.

(define (software-type) 'UNIX)

;;; (scheme-implementation-type) should return the name of the scheme
;;; implementation loading this file.

(define (scheme-implementation-type) 'Scheme48)

;;; (scheme-implementation-home-page) should return a (string) URI
;;; (Uniform Resource Identifier) for this scheme implementation's home
;;; page; or false if there isn't one.

(define (scheme-implementation-home-page) "http://s48.org/")

;;; (scheme-implementation-version) should return a string describing
;;; the version of the scheme implementation loading this file.

(define scheme-implementation-version
  (let ((version (getenv "S48_VERSION")))
    (lambda () version)))

;;; (implementation-vicinity) should be defined to be the pathname of
;;; the directory where any auxiliary files to your Scheme
;;; implementation reside.

(define implementation-vicinity
  (let ((vic (getenv "S48_VICINITY")))
    (lambda () vic)))

;;; (library-vicinity) should be defined to be the pathname of the
;;; directory where files of Scheme library functions reside.

(define library-vicinity
  (let ((vic (getenv "SCHEME_LIBRARY_PATH")))
    (lambda () vic)))

;;; (home-vicinity) should return the vicinity of the user's HOME
;;; directory, the directory which typically contains files which
;;; customize a computer environment for a user.

(define home-vicinity
  (let ((home-path (getenv "HOME")))
    (lambda () home-path)))

(let* ((siv (scheme-implementation-version))
       (num-ver (and siv (string->number siv))))
  (cond ((not num-ver))
	((>= num-ver 0.54)
	 (set! system #f))))

;;; *FEATURES* should be set to a list of symbols describing features
;;; of this implementation.  See Template.scm for the list of feature
;;; names.

(define *features*
      '(
	source				;can load scheme source files
					;(slib:load-source "filename")
;	compiled			;can load compiled files
					;(slib:load-compiled "filename")

		       ;; Scheme report features

	rev5-report			;conforms to
	eval				;R5RS two-argument eval
	values				;R5RS multiple values
	dynamic-wind			;R5RS dynamic-wind
	macro				;R5RS high level macros
	delay				;has DELAY and FORCE
	multiarg-apply			;APPLY can take more than 2 args.
	char-ready?
	rationalize
	rev4-optional-procedures	;LIST-TAIL, STRING->LIST,
					;LIST->STRING, STRING-COPY,
					;STRING-FILL!, LIST->VECTOR,
					;VECTOR->LIST, and VECTOR-FILL!

	rev4-report			;conforms to

	ieee-p1178			;conforms to

;	rev3-report			;conforms to

;	rev2-procedures			;SUBSTRING-MOVE-LEFT!,
					;SUBSTRING-MOVE-RIGHT!,
					;SUBSTRING-FILL!,
					;STRING-NULL?, APPEND!, 1+,
					;-1+, <?, <=?, =?, >?, >=?
;	object-hash			;has OBJECT-HASH

;	multiarg/and-			;/ and - can take more than 2 args.
	with-file			;has WITH-INPUT-FROM-FILE and
					;WITH-OUTPUT-FROM-FILE
;	transcript			;TRANSCRIPT-ON and TRANSCRIPT-OFF
;	ieee-floating-point		;conforms to IEEE Standard 754-1985
					;IEEE Standard for Binary
					;Floating-Point Arithmetic.
	full-continuation		;can return multiple times

			;; Other common features

;	srfi				;srfi-0, COND-EXPAND finds all srfi-*
;	sicp				;runs code from Structure and
					;Interpretation of Computer
					;Programs by Abelson and Sussman.
	defmacro			;has Common Lisp DEFMACRO
;	record				;has user defined data structures
;	string-port			;has CALL-WITH-INPUT-STRING and
					;CALL-WITH-OUTPUT-STRING
;	sort
;	pretty-print
;	object->string
;	format				;Common-lisp output formatting
;	trace				;has macros: TRACE and UNTRACE
;	compiler			;has (COMPILER)
;	ed				;(ED) is editor
	system				;posix (system <string>)
	getenv				;posix (getenv <string>)
;	program-arguments		;returns list of strings (argv)
;	current-time			;returns time in seconds since 1/1/1970
		  ;; Implementation Specific features
	))

;;; (OUTPUT-PORT-WIDTH <port>)
(define (output-port-width . arg) 79)

;;; (OUTPUT-PORT-HEIGHT <port>)
(define (output-port-height . arg) 24)

;;; (CURRENT-ERROR-PORT)
(define current-error-port s48-current-error-port)

;;; (TMPNAM) makes a temporary file name.
(define tmpnam
  (let ((cntr 100))
    (lambda () (set! cntr (+ 1 cntr))
	    (let ((tmp (string-append "slib_" (number->string cntr))))
	      (if (file-exists? tmp) (tmpnam) tmp)))))

;;; (FILE-EXISTS? <string>)
(define (file-exists? f)
  (call-with-current-continuation
   (lambda (k)
     (s48-with-handler
      (lambda (condition decline)
	(k #f))
      (lambda ()
	(close-input-port (open-input-file f))
	#t)))))

;;; (DELETE-FILE <string>)
(define (delete-file file-name)
  (system (string-append "rm " file-name)))

;;; FORCE-OUTPUT flushes any pending output on optional arg output port
;;; use this definition if your system doesn't have such a procedure.
(define (force-output . arg)
  (s48-force-output
   (if (null? arg) (current-output-port) (car arg))))

;;; "rationalize" adjunct procedures.
(define (find-ratio x e)
  (let ((rat (rationalize x e)))
    (list (numerator rat) (denominator rat))))
(define (find-ratio-between x y)
  (find-ratio (/ (+ x y) 2) (/ (- x y) 2)))

;;; CHAR-CODE-LIMIT is one greater than the largest integer which can
;;; be returned by CHAR->INTEGER.
(define integer->char s48-ascii->char)
(define char->integer
  (let ((char->integer char->integer)
	(code0 (char->integer (integer->char 0))))
    (lambda (char) (- (char->integer char) code0))))
(define char-code-limit 256)

;;; Workaround MODULO bug
(define modulo
  (let ((modulo modulo))
    (lambda (n1 n2)
      (let ((ans (modulo n1 n2)))
	(if (= ans n2) (- ans ans) ans)))))

;;; Workaround atan bug
(define two-arg:atan atan)
(define (atan y . x)
  (if (null? x) (two-arg:atan y 1) (two-arg:atan y (car x))))

;;; MOST-POSITIVE-FIXNUM is used in modular.scm
(define most-positive-fixnum #x1FFFFFFF)

;;; Return argument
(define (identity x) x)

;;; SLIB:EVAL is single argument eval using the top-level (user) environment.
(define slib:eval
  (let ((eval eval)
	(interaction-environment interaction-environment))
    (lambda (form)
      (eval form (interaction-environment)))))

;;; If your implementation provides R4RS macros:
(define macro:eval slib:eval)
(define (macro:load <pathname>)
  (if (not (file-exists? <pathname>))
      (set! <pathname> (string-append <pathname> (scheme-file-suffix))))
  (load <pathname>))

(define *defmacros*
  (list (cons 'defmacro
	      (lambda (name parms . body)
		`(set! *defmacros* (cons (cons ',name (lambda ,parms ,@body))
					 *defmacros*))))))
(define (defmacro? m) (and (assq m *defmacros*) #t))

(define (macroexpand-1 e)
  (if (pair? e)
      (let ((a (car e)))
	(cond ((symbol? a) (set! a (assq a *defmacros*))
	       (if a (apply (cdr a) (cdr e)) e))
	      (else e)))
      e))

(define (macroexpand e)
  (if (pair? e)
      (let ((a (car e)))
	(cond ((symbol? a)
	       (set! a (assq a *defmacros*))
	       (if a (macroexpand (apply (cdr a) (cdr e))) e))
	      (else e)))
      e))

(define gentemp
  (let ((*gensym-counter* -1))
    (lambda ()
      (set! *gensym-counter* (+ *gensym-counter* 1))
      (string->symbol
       (string-append "slib:G" (number->string *gensym-counter*))))))

(define base:eval slib:eval)
(define (defmacro:eval x) (base:eval (defmacro:expand* x)))

(define defmacro:load macro:load)

(define (slib:eval-load <pathname> evl)
  (if (not (file-exists? <pathname>))
      (set! <pathname> (string-append <pathname> (scheme-file-suffix))))
  (call-with-input-file <pathname>
    (lambda (port)
      (let ((old-load-pathname *load-pathname*))
	(set! *load-pathname* <pathname>)
	(do ((o (read port) (read port)))
	    ((eof-object? o))
	  (evl o))
	(set! *load-pathname* old-load-pathname)))))

(define slib:warn
  (lambda args
    (let ((cep (current-error-port)))
      ;;(if (provided? 'trace) (print-call-stack cep))
      (display "Warn: " cep)
      (for-each (lambda (x) (display x cep)) args))))

;;; define an error procedure for the library
(define (slib:error . args)
  ;;(if (provided? 'trace) (print-call-stack (current-error-port)))
  (apply s48-error args))

;;; define these as appropriate for your system.
(define slib:tab (s48-ascii->char 9))
(define slib:form-feed (s48-ascii->char 12))

;;; Support for older versions of Scheme.  Not enough code for its own file.
(define (last-pair l) (if (pair? (cdr l)) (last-pair (cdr l)) l))
(define t #t)
(define nil #f)

;;; Define these if your implementation's syntax can support them and if
;;; they are not already defined.

(define (1+ n) (+ n 1))
(define (-1+ n) (+ n -1))
;(define 1- -1+)

(define in-vicinity string-append)

;;; Define SLIB:EXIT to be the implementation procedure to exit or
;;; return if exitting not supported.
(define slib:exit (lambda args #f))

;;; Here for backward compatability
(define scheme-file-suffix
  (case (software-type)
    ((NOSVE) (lambda () "_scm"))
    (else (lambda () ".scm"))))

;;; (SLIB:LOAD-SOURCE "foo") should load "foo.scm" or with whatever
;;; suffix all the module files in SLIB have.  See feature 'SOURCE.

(define (slib:load-source f) (load (string-append f (scheme-file-suffix))))

;;; (SLIB:LOAD-COMPILED "foo") should load the file that was produced
;;; by compiling "foo.scm" if this implementation can compile files.
;;; See feature 'COMPILED.

(define slib:load-compiled load)

;;; At this point SLIB:LOAD must be able to load SLIB files.

(define slib:load slib:load-source)

;;; Scheme48 complains that these are not defined (even though they
;;; won't be called until they are).
(define synclo:load #f)
(define syncase:load #f)
(define macwork:load #f)
(define transcript-on #f)
(define transcript-off #f)

;;; Jacques Mequin wins the Spring 2001 SLIB extreme cleverness award:
(define-syntax defmacro
  (lambda (e r c)
    (let* ((e-fields (cdr e))
	   (macro-name (car e-fields))
	   (macro-args (cdr e-fields))
	   (slib-store (eval 'defmacro:eval (interaction-environment))))
      (slib-store `(defmacro ,macro-name ,@macro-args)))
    `(define-syntax ,(cadr e)
       (lambda (em rm cm)
	 (let ((macro-name ',(cadr e))
	       (macro-args (cdr em))
	       (slib-eval (eval 'macroexpand-1 (interaction-environment))))
	   (slib-eval `(,macro-name ,@macro-args)))))))

(slib:load (in-vicinity (library-vicinity) "require"))

;;; Needed to support defmacro
(require 'defmacroexpand)
(define *args* '())
(define (program-arguments) (cons "scheme48" *args*))
(set! *catalog* #f)

,collect
,batch off
,dump slib.image "(slib 2d2)"
,exit