ice-9/debugger/state.scm

   1 ;;;; (ice-9 debugger state) -- debugger state representation
   2
   3 ;;; Copyright (C) 2002 Free Software Foundation, Inc.
   4 ;;;
   5 ;;; This program is free software; you can redistribute it and/or
   6 ;;; modify it under the terms of the GNU General Public License as
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   8 ;;; (at your option) any later version.
   9 ;;;
  10 ;;; This program is distributed in the hope that it will be useful,
  11 ;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 ;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13 ;;; General Public License for more details.
  14 ;;;
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  19 ;;;
  20 ;;; As a special exception, the Free Software Foundation gives permission
  21 ;;; for additional uses of the text contained in its release of GUILE.
  22 ;;;
  23 ;;; The exception is that, if you link the GUILE library with other files
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  25 ;;; resulting executable to be covered by the GNU General Public License.
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  43
  44 (define-module (ice-9 debugger state)
  45   #:export (make-state
  46             state-stack
  47             state-index
  48             state-flags
  49             set-stack-index!))
  50
  51 (define state-rtd (make-record-type "debugger-state" '(stack index flags)))
  52 (define state? (record-predicate state-rtd))
  53 (define make-state
  54   (let ((make-state-internal (record-constructor state-rtd
  55                                                  '(stack index flags))))
  56     (lambda (stack index . flags)
  57       (make-state-internal stack index flags))))
  58 (define state-stack (record-accessor state-rtd 'stack))
  59 (define state-index (record-accessor state-rtd 'index))
  60 (define state-flags (record-accessor state-rtd 'flags))
  61
  62 (define set-state-index! (record-modifier state-rtd 'index))
  63
  64 (define (set-stack-index! state index)
  65   (let* ((stack (state-stack state))
  66          (ssize (stack-length stack)))
  67     (set-state-index! state
  68                       (cond ((< index 0) 0)
  69                             ((>= index ssize) (- ssize 1))
  70                             (else index)))))
  71
  72 ;;; (ice-9 debugger state) ends here.