;;;"gambit.init" Initialisation for SLIB for Gambit	-*-scheme-*-
;;; Copyright (C) 1991, 1992, 1993, 1994, 1997 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.

;;; Updated 1992 February 1 for Gambit v1.71 -- by Ken Dickey
;;; Date: Wed, 12 Jan 1994 15:03:12 -0500
;;; From: barnett@armadillo.urich.edu (Lewis Barnett)
;;; Relative pathnames for Slib in MacGambit
;;; Hacked yet again for Gambit v2.4, Jan 1997, by Mike Pope

(define (software-type) 'UNIX)		; 'MACOS for MacGambit.

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

(define (scheme-implementation-version) "2.4")

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

(define implementation-vicinity
  (case (software-type)
    ((UNIX)	(lambda () "/usr/local/src/scheme/"))
    ((VMS)	(lambda () "scheme$src:"))
    ((MS-DOS)	(lambda () "C:\\scheme\\"))
    ((WINDOWS)  (lambda () "c:/scheme/"))
    ((MACOS)
     (let ((arg0 (list-ref (argv) 0)))
       (let loop ((i (- (string-length arg0) 1)))
	 (cond ((negative? i) "")
	       ((char=? #\: (string-ref arg0 i))
		(set! arg0 (substring arg0 0 (+ i 1)))
		(lambda () arg0))
	       (else (loop (- i 1)))))))))

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

;;; This assumes that the slib files are in a folder
;;; called slib in the same directory as the MacGambit Interpreter.

(define library-vicinity
  (let ((library-path
	 (case (software-type)
	   ((UNIX) "/usr/local/lib/slib/")
	   ((MACOS) (string-append (implementation-vicinity) ":slib:"))
	   ((AMIGA)	"dh0:scm/Library/")
	   ((VMS) "lib$scheme:")
	   ((WINDOWS MS-DOS) "C:\\SLIB\\")
	   (else ""))))
    (lambda () library-path)))

;;; (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) #f)

;;; *FEATURES* should be set to a list of symbols describing features
;;; of this implementation.  Suggestions for features are:

(define *features*
      '(
	source				;can load scheme source files
					;(slib:load-source "filename")
	compiled			;can load compiled files
					;(slib:load-compiled "filename")
	rev4-report			;conforms to
;	rev3-report			;conforms to
	ieee-p1178			;conforms to
	sicp				;runs code from Structure and
					;Interpretation of Computer
					;Programs by Abelson and Sussman.
	rev4-optional-procedures	;LIST-TAIL, STRING->LIST,
					;LIST->STRING, STRING-COPY,
					;STRING-FILL!, LIST->VECTOR,
					;VECTOR->LIST, and VECTOR-FILL!
;	rev2-procedures			;SUBSTRING-MOVE-LEFT!,
					;SUBSTRING-MOVE-RIGHT!,
					;SUBSTRING-FILL!,
					;STRING-NULL?, APPEND!, 1+,
					;-1+, <?, <=?, =?, >?, >=?
	multiarg/and-			;/ and - can take more than 2 args.
	multiarg-apply			;APPLY can take more than 2 args.
	rationalize
	delay				;has DELAY and FORCE
	with-file			;has WITH-INPUT-FROM-FILE and
					;WITH-OUTPUT-FROM-FILE
;	string-port			;has CALL-WITH-INPUT-STRING and
					;CALL-WITH-OUTPUT-STRING
	transcript			;TRANSCRIPT-ON and TRANSCRIPT-OFF
	char-ready?
;	macro				;has R4RS high level macros
	defmacro			;has Common Lisp DEFMACRO
	eval				;SLIB:EVAL is single argument eval
;	record				;has user defined data structures
;	values				;proposed multiple values
;	dynamic-wind			;proposed dynamic-wind
	ieee-floating-point		;conforms to
	full-continuation		;can return multiple times
;	object-hash			;has OBJECT-HASH

;	sort
;	queue				;queues
	pretty-print
;	object->string
;	format
	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)
;	Xwindows			;X support
;	curses				;screen management package
;	termcap				;terminal description package
;	terminfo			;sysV terminal description
;	current-time			;returns time in seconds since 1/1/1970
    ))

;;; (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
  (let ((port (current-output-port)))
    (lambda () port)))

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

;;; Gambit supports SYSTEM as an "Unstable Addition"; Watch for changes.
(define system ##shell-command)

;;; (FILE-EXISTS? <string>)
;(define (file-exists? f) #f)

;;; (DELETE-FILE <string>)
(define (delete-file f) #f)

;;; 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 flush-output)

;;; CALL-WITH-INPUT-STRING and CALL-WITH-OUTPUT-STRING are the string
;;; port versions of CALL-WITH-*PUT-FILE.

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

;; MOST-POSITIVE-FIXNUM is used in modular.scm
(define most-positive-fixnum #x1FFFFFFF) ; 3-bit tag for 68K

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

;;; If your implementation provides eval SLIB:EVAL is single argument
;;; eval using the top-level (user) environment.
(define slib:eval eval)

; Define program-arguments as argv
(define program-arguments argv)

;;; If your implementation provides R4RS macros:
;(define macro:eval slib:eval)
;(define macro:load load)

; Set up defmacro in terms of gambit's define-macro
(define-macro (defmacro name args . body)
  `(define-macro (,name ,@args) ,@body))

(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 base:eval)

(define (defmacro:load <pathname>)
  (slib:eval-load <pathname> defmacro:eval))

(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 ((port (current-error-port)))
      (display "Warn: " port)
      (for-each (lambda (x) (display x port)) args))))

;; define an error procedure for the library
(define slib:error error)

;; define these as appropriate for your system.
(define slib:tab (integer->char 9))
(define slib:form-feed (integer->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 it 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 (exit)))

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

;;; (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 load)

;;; (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)

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