diff -r 620fd98a021d -r 44ff2a6fcadc absyntax_utils/case_element_iterator.cc
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/absyntax_utils/case_element_iterator.cc	Fri Sep 02 18:15:55 2011 +0200
@@ -0,0 +1,186 @@
+/*
+ *  matiec - a compiler for the programming languages defined in IEC 61131-3
+ *
+ *  Copyright (C) 2003-2011  Mario de Sousa (msousa@fe.up.pt)
+ *  Copyright (C) 2007-2011  Laurent Bessard and Edouard Tisserant
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ *
+ * This code is made available on the understanding that it will not be
+ * used in safety-critical situations without a full and competent review.
+ */
+
+/*
+ * An IEC 61131-3 compiler.
+ *
+ * Based on the
+ * FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10)
+ *
+ */
+
+
+/*
+ * Case element iterator.
+ * Iterate through the elements of a case list.
+ *
+ * This is part of the 4th stage that generates
+ * a c++ source program equivalent to the IL and ST
+ * code.
+ */
+
+/* Given a case_list_c and a type of element, iterate through
+ * each element, returning the symbol of each element if from
+ * the good type...case_element_iterator_c
+ */
+
+
+
+
+#include "case_element_iterator.hh"
+
+
+//#define DEBUG
+#ifdef DEBUG
+#define TRACE(classname) printf("\n____%s____\n",classname);
+#else
+#define TRACE(classname)
+#endif
+
+
+#define ERROR error_exit(__FILE__,__LINE__)
+/* function defined in main.cc */
+extern void error_exit(const char *file_name, int line_no);
+
+
+void* case_element_iterator_c::handle_case_element(symbol_c *case_element) {
+  if (current_case_element == case_element) {
+    current_case_element = NULL;
+  }
+  else if (current_case_element == NULL) {
+	current_case_element = case_element;
+	return case_element;
+  }
+
+  /* Not found! */
+  return NULL;
+}
+
+void* case_element_iterator_c::iterate_list(list_c *list) {
+  void *res;
+  for (int i = 0; i < list->n; i++) {
+    res = list->elements[i]->accept(*this);
+    if (res != NULL)
+        return res;
+  }
+  return NULL;
+}
+
+/* start off at the first case element once again... */
+void case_element_iterator_c::reset(void) {
+  current_case_element = NULL;
+}
+
+
+/* initialise the iterator object.
+ * We must be given a reference to a case_list_c that will be analysed...
+ */
+case_element_iterator_c::case_element_iterator_c(symbol_c *list, case_element_t element_type) {
+  /* do some consistency check... */
+  case_list_c* case_list = dynamic_cast<case_list_c*>(list);
+
+  if (NULL == case_list) ERROR;
+
+  /* OK. Now initialise this object... */
+  this->case_list = list;
+  this->wanted_element_type = element_type;
+  reset();
+}
+
+
+
+/* Skip to the next case element of type chosen. After object creation,
+ * the object references on case element _before_ the first, so
+ * this function must be called once to get the object to
+ * reference the first element...
+ *
+ * Returns the case element's symbol!
+ */
+symbol_c *case_element_iterator_c::next(void) {
+  void *res = case_list->accept(*this);
+  if (res == NULL) 
+    return NULL;
+
+  return current_case_element;
+}
+
+/******************************/
+/* B 1.2.1 - Numeric Literals */
+/******************************/
+void *case_element_iterator_c::visit(integer_c *symbol) {
+  switch (wanted_element_type) {
+	case element_single:
+	  return handle_case_element(symbol);
+	  break;
+	default:
+	  break;
+  }
+  return NULL;
+}
+
+void *case_element_iterator_c::visit(neg_integer_c *symbol) {
+  switch (wanted_element_type) {
+	case element_single:
+	  return handle_case_element(symbol);
+	  break;
+	default:
+	  break;
+  }
+  return NULL;
+}
+
+/********************************/
+/* B 1.3.3 - Derived data types */
+/********************************/
+/*  signed_integer DOTDOT signed_integer */
+void *case_element_iterator_c::visit(subrange_c *symbol) {
+  switch (wanted_element_type) {
+    case element_subrange:
+      return handle_case_element(symbol);
+      break;
+    default:
+      break;
+  }
+  return NULL;
+}
+
+/* enumerated_type_name '#' identifier */
+void *case_element_iterator_c::visit(enumerated_value_c *symbol) {
+  switch (wanted_element_type) {
+    case element_single:
+      return handle_case_element(symbol);
+      break;
+    default:
+      break;
+  }
+  return NULL;
+}
+
+/********************************/
+/* B 3.2.3 Selection Statements */
+/********************************/
+void *case_element_iterator_c::visit(case_list_c *symbol) {
+  return iterate_list(symbol);
+}
+