Update comments on general architecture.
/*
* 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 "../absyntax/visitor.hh"
class case_element_iterator_c : public null_visitor_c {
public:
/* A type to specify the type of element.
*/
typedef enum {
element_single,
element_subrange,
} case_element_t ;
private:
/* a pointer to the case_list_c currently being analyzed */
symbol_c *case_list;
/* used when called to iterate() for a parameter */
symbol_c *current_case_element;
/* used to indicate the type of case element on which iterate */
case_element_t wanted_element_type;
private:
void* handle_case_element(symbol_c *case_element);
void* iterate_list(list_c *list);
public:
/* start off at the first case element once again... */
void reset(void);
/* initialize the iterator object.
* We must be given a reference to a case_list_c that will be analyzed...
*/
case_element_iterator_c(symbol_c *list, case_element_t element_type);
/* 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 *next(void);
private:
/******************************/
/* B 1.2.1 - Numeric Literals */
/******************************/
void *visit(integer_c *symbol);
void *visit(neg_integer_c *symbol);
/********************************/
/* B 1.3.3 - Derived data types */
/********************************/
/* signed_integer DOTDOT signed_integer */
void *visit(subrange_c *symbol);
/* enumerated_type_name '#' identifier */
void *visit(enumerated_value_c *symbol);
/********************************/
/* B 3.2.3 Selection Statements */
/********************************/
void *visit(case_list_c *symbol);
}; // function_param_iterator_c