;;;; lazy-ffi.scm
;
; Copyright (c) 2000-2011, Felix L. Winkelmann
; All rights reserved.
;
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; conditions are met:
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;     disclaimer. 
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(require-library srfi-69)


(define lazy-ffi:*symbols* (make-hash-table))

(define (lazy-ffi:generate-uid s)
  (or (hash-table-ref/default lazy-ffi:*symbols* s #f)
      (let ([uid (string->symbol (conc "lazy-ffi:" (current-seconds) (random #x1000000)))])
	(hash-table-set! lazy-ffi:*symbols* s uid)
	uid) ) )

(define (lazy-ffi:read port)
  (if (eq? (peek-char port) #\~)
      (begin
	(read-char port)
	`(lazy-ffi:function-ptr ,(read port)) )
      (let ([x (read port)])
	(define (process x)
	  (cond [(or (not x) (string? x)) `(lazy-ffi:module ,x)]
		[(symbol? x) `(lazy-ffi:function ',x ',(lazy-ffi:generate-uid x))]
		[(list? x) `(list ,@(map process x))]
		[else (syntax-error "invalid use of `#~'" x)] ) )
	(process x) ) ) )

(set-sharp-read-syntax! #\~ lazy-ffi:read)