ice-9/debugger/state.scm

   1 ;;;; (ice-9 debugger state) -- debugger state representation
   2
   3 ;;; Copyright (C) 2002, 2006 Free Software Foundation, Inc.
   4 ;;;
   5 ;; This library is free software; you can redistribute it and/or
   6 ;; modify it under the terms of the GNU Lesser General Public
   7 ;; License as published by the Free Software Foundation; either
   8 ;; version 2.1 of the License, or (at your option) any later version.
   9 ;;
  10 ;; This library 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 ;; Lesser General Public License for more details.
  14 ;;
  15 ;; You should have received a copy of the GNU Lesser General Public
  16 ;; License along with this library; if not, write to the Free Software
  17 ;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  18
  19 (define-module (ice-9 debugger state)
  20   #:export (make-state
  21             state-stack
  22             state-index
  23             state-flags
  24             set-stack-index!))
  25
  26 (define state-rtd (make-record-type "debugger-state" '(stack index flags)))
  27 (define state? (record-predicate state-rtd))
  28 (define make-state
  29   (let ((make-state-internal (record-constructor state-rtd
  30                                                  '(stack index flags))))
  31     (lambda (stack index . flags)
  32       (make-state-internal stack index flags))))
  33 (define state-stack (record-accessor state-rtd 'stack))
  34 (define state-index (record-accessor state-rtd 'index))
  35 (define state-flags (record-accessor state-rtd 'flags))
  36
  37 (define set-state-index! (record-modifier state-rtd 'index))
  38
  39 (define (set-stack-index! state index)
  40   (let* ((stack (state-stack state))
  41          (ssize (stack-length stack)))
  42     (set-state-index! state
  43                       (cond ((< index 0) 0)
  44                             ((>= index ssize) (- ssize 1))
  45                             (else index)))))
  46
  47 ;;; (ice-9 debugger state) ends here.