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/*

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 *  matiec - a compiler for the programming languages defined in IEC 61131-3

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 *  Copyright (C) 2003-2011  Mario de Sousa (msousa@fe.up.pt)

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 *  Copyright (C) 2007-2011  Laurent Bessard and Edouard Tisserant

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 *

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 *  This program is free software: you can redistribute it and/or modify

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 *  it under the terms of the GNU General Public License as published by

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 *  the Free Software Foundation, either version 3 of the License, or

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 *  (at your option) any later version.

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 *

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 *  This program is distributed in the hope that it will be useful,

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 *  but WITHOUT ANY WARRANTY; without even the implied warranty of

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 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

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 *  GNU General Public License for more details.

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 *

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 *  You should have received a copy of the GNU General Public License

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 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.

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 *

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 *

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 * This code is made available on the understanding that it will not be

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 * used in safety-critical situations without a full and competent review.

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 */

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/*

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 * An IEC 61131-3 compiler.

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 *

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 * Based on the

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 * FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10)

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 *

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 */

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/*

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 * Definition of the Abstract Syntax data structure components

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 */

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/*

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 * ABSYNTAX.DEF

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 *

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 * This generates the parse tree structure used to bind the components

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 * identified by Bison in the correct syntax order. At the end of the

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 * Bison analysis the tree is walked in a sequential fashion generating

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 * the relavent code.

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 */

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/*****************************************************************/

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/*****************************************************************/

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/*****************************************************************/

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/*****************************************************************/

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/*                                                               */

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/*      safe<xxxxxx> Symbols are defined in:                     */

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/*      PLCopen - Technical Committee 5                          */

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/*      Safety Software Technical Specification,                 */

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/*      Part 1: Concepts and Function Blocks,                    */

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/*      Version 1.0 – Official Release - 2006-01-31              */

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/*                                                               */

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/*****************************************************************/

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/*****************************************************************/

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/*****************************************************************/

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/*****************************************************************/

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/*****************************************************************/

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/*****************************************************************/

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/*****************************************************************/

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/*****************************************************************/

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/*                                                               */

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/*             Symbols defined in:                               */

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/*      FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10)          */

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/*                                                               */

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/*****************************************************************/

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/*****************************************************************/

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/*****************************************************************/

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/*****************************************************************/

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/* Based on the                                    */

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/* FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10) */

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/* EN/ENO */

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/* NOTE we store 'EN' and 'ENO' tokens in an identifier_c

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 *      as they may be used as variables, and it is much easier 

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 *      to handle them (fewer special cases) if we do it that way...

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 */

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/*

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SYM_REF0(en_param_c)

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SYM_REF0(eno_param_c)

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*/

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/* A class used to identify an entry (literal, variable, etc...) in the abstract syntax tree with an invalid data type */

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/* This is only used from stage3 onwards. Stages 1 and 2 will never create any instances of invalid_type_name_c */

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SYM_REF0(invalid_type_name_c)

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/********************/

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/* 2.1.6 - Pragmas  */

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/********************/

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SYM_REF0(disable_code_generation_pragma_c)

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SYM_REF0(enable_code_generation_pragma_c)

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SYM_TOKEN(pragma_c)

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/***************************/

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/* B 0 - Programming Model */

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/***************************/

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/* enumvalue_symtable is filled in by enum_declaration_check_c, during stage3 semantic verification, with a list of all enumerated constants declared inside this POU */

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SYM_LIST(library_c, enumvalue_symtable_t enumvalue_symtable;)

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/*************************/

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/* B.1 - Common elements */

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/*************************/

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/*******************************************/

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/* B 1.1 - Letters, digits and identifiers */

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/*******************************************/

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SYM_TOKEN(identifier_c)

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/* A special identifier class, used for identifiers that have been previously declared as a derived datatype */

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/*  This is currently needed because generate_c stage 4 needs to handle the array datatype identifiers differently to all other identifiers. */

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SYM_TOKEN(derived_datatype_identifier_c) 

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/*********************/

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/* B 1.2 - Constants */

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/*********************/

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/*********************************/

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/* B 1.2.XX - Reference Literals */

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/*********************************/

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/* defined in IEC 61131-3 v3 - Basically the 'NULL' keyword! */

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SYM_REF0(ref_value_null_literal_c)

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/******************************/

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/* B 1.2.1 - Numeric Literals */

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/******************************/

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SYM_TOKEN(real_c)

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SYM_TOKEN(integer_c)

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SYM_TOKEN(binary_integer_c)

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SYM_TOKEN(octal_integer_c)

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SYM_TOKEN(hex_integer_c)

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/* Note:

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 * We do not have signed_integer_c and signed_real_c classes.

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 * These are stored in the parse tree as a integer_c or real_c

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 * preceded by a unary minus operator if they are inside an expression,

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 * or a neg_integer_c and neg_real_c when used outside an ST expression.

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 */

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/* Not required:

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SYM_TOKEN(signed_integer_c)

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SYM_TOKEN(signed_real_c)

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*/

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/* NOTE: literal __values__ are stored directly in classes such as:

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 *          - real_c

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 *          - integer_c

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 *          - binary_integer_c

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 *          - etc...

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 *

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 *       However, for both the real_c and the integer_c, if they are preceded 

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 *       by a '-' negation sign, they are further encapsulated inside 

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 *       a neg_literal_c (i.e. the neg_literal_c will point to the 

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 *       real_c or integer_c with the value being negated.

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 *          neg_literal_c -> integer_literal_c

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 *                OR

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 *          neg_literal_c -> real_literal_c

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 *

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 *       However, this has since been changed to...

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 *        - replace the neg_literal_c with two distinc classes

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 *              (neg_integer_c and neg_real_c), one for each

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 *              lietral type. 

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 *

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 *       This change was done in order to ease the writing of semantic verification (stage3) code.

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 *       However, that version of the code has since been replaced by a newer and better algoritm.

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 *       This means the above change can now be undone, but there is really no need to undo it,

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 *       so we leave it as it is.

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 */  

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SYM_REF1(neg_real_c, exp)

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SYM_REF1(neg_integer_c, exp)

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/* Not required:

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SYM_REF2(numeric_literal_c, type, value)

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*/

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SYM_REF2(integer_literal_c, type, value)

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SYM_REF2(real_literal_c, type, value)

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SYM_REF2(bit_string_literal_c, type, value)

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/* A typed or untyped boolean literal... */

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/* type may be NULL */

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SYM_REF2(boolean_literal_c, type, value)

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/* helper class for boolean_literal_c */

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SYM_REF0(boolean_true_c)

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/* helper class for boolean_literal_c */

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SYM_REF0(boolean_false_c)

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/*******************************/

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/* B.1.2.2   Character Strings */

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/*******************************/

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SYM_TOKEN(double_byte_character_string_c)

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SYM_TOKEN(single_byte_character_string_c)

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/***************************/

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/* B 1.2.3 - Time Literals */

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/***************************/

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/************************/

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/* B 1.2.3.1 - Duration */

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/************************/

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SYM_REF0(neg_time_c)

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SYM_REF3(duration_c, type_name, neg, interval)

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SYM_REF5(interval_c, days, hours, minutes, seconds, milliseconds)

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SYM_TOKEN(fixed_point_c)

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/*

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SYM_REF2(days_c, days, hours)

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SYM_REF2(hours_c, hours, minutes)

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SYM_REF2(minutes_c, minutes, seconds)

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SYM_REF2(seconds_c, seconds, milliseconds)

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SYM_REF1(milliseconds_c, milliseconds)

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*/

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/************************************/

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/* B 1.2.3.2 - Time of day and Date */

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/************************************/

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SYM_REF2(time_of_day_c, type_name, daytime)

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SYM_REF3(daytime_c, day_hour, day_minute, day_second)

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SYM_REF2(date_c, type_name, date_literal)

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SYM_REF3(date_literal_c, year, month, day)

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SYM_REF3(date_and_time_c, type_name, date_literal, daytime)

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/**********************/

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/* B.1.3 - Data types */

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/**********************/

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/***********************************/

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/* B 1.3.1 - Elementary Data Types */

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/***********************************/

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SYM_REF0(time_type_name_c)

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SYM_REF0(bool_type_name_c)

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SYM_REF0(sint_type_name_c)

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SYM_REF0(int_type_name_c)

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SYM_REF0(dint_type_name_c)

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SYM_REF0(lint_type_name_c)

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SYM_REF0(usint_type_name_c)

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SYM_REF0(uint_type_name_c)

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SYM_REF0(udint_type_name_c)

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SYM_REF0(ulint_type_name_c)

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SYM_REF0(real_type_name_c)

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SYM_REF0(lreal_type_name_c)

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SYM_REF0(date_type_name_c)

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SYM_REF0(tod_type_name_c)

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SYM_REF0(dt_type_name_c)

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SYM_REF0(byte_type_name_c)

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SYM_REF0(word_type_name_c)

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SYM_REF0(dword_type_name_c)

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SYM_REF0(lword_type_name_c)

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SYM_REF0(string_type_name_c)

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SYM_REF0(wstring_type_name_c)

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  /*****************************************************************/

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  /* Keywords defined in "Safety Software Technical Specification" */

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  /*****************************************************************/

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SYM_REF0(safetime_type_name_c)

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SYM_REF0(safebool_type_name_c)

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SYM_REF0(safesint_type_name_c)

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SYM_REF0(safeint_type_name_c)

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SYM_REF0(safedint_type_name_c)

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SYM_REF0(safelint_type_name_c)

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SYM_REF0(safeusint_type_name_c)

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SYM_REF0(safeuint_type_name_c)

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SYM_REF0(safeudint_type_name_c)

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SYM_REF0(safeulint_type_name_c)

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SYM_REF0(safereal_type_name_c)

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SYM_REF0(safelreal_type_name_c)

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SYM_REF0(safedate_type_name_c)

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SYM_REF0(safetod_type_name_c)

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SYM_REF0(safedt_type_name_c)

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SYM_REF0(safebyte_type_name_c)

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SYM_REF0(safeword_type_name_c)

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SYM_REF0(safedword_type_name_c)

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SYM_REF0(safelword_type_name_c)

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SYM_REF0(safestring_type_name_c)

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SYM_REF0(safewstring_type_name_c)

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/********************************/

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/* B.1.3.2 - Generic data types */

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/********************************/

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/* ANY is currently only allowed when defining REF_TO ANY datatypes

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 * (equivalent to a (void *)). This is a non standard extension to the

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 * standard.

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 * Standard library function that use the generic datatypes (ANY_***) are

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 * currently handed as overloaded functions, and do not therefore require

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 * the use of the generic datatype keywords.

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 */

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SYM_REF0(generic_type_any_c)            // ANY

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/*

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SYM_REF0(generic_type_any_derived_c)    // ANY_DERIVED

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SYM_REF0(generic_type_any_elementary_c) // ANY_ELEMENTARY

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SYM_REF0(generic_type_any_magnitude_c)  // ANY_MAGNITUDE

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SYM_REF0(generic_type_any_num_c)        // ANY_NUM

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SYM_REF0(generic_type_any_real_c)       // ANY_REAL

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SYM_REF0(generic_type_any_int_c)        // ANY_INT

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SYM_REF0(generic_type_any_bit_c)        // ANY_BIT

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SYM_REF0(generic_type_any_string_c)     // ANY_STRING

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SYM_REF0(generic_type_any_date_c)       // ANY_DATE

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*/

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/********************************/

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/* B 1.3.3 - Derived data types */

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/********************************/

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/*  TYPE type_declaration_list END_TYPE */

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SYM_REF1(data_type_declaration_c, type_declaration_list)

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/* helper symbol for data_type_declaration */

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SYM_LIST(type_declaration_list_c)

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/*  simple_type_name ':' simple_spec_init */

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SYM_REF2(simple_type_declaration_c, simple_type_name, simple_spec_init)

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/* simple_specification ASSIGN constant */

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SYM_REF2(simple_spec_init_c, simple_specification, constant)

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/*  subrange_type_name ':' subrange_spec_init */

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SYM_REF2(subrange_type_declaration_c, subrange_type_name, subrange_spec_init)

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/* subrange_specification ASSIGN signed_integer */

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SYM_REF2(subrange_spec_init_c, subrange_specification, signed_integer)

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/*  integer_type_name '(' subrange')' */

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SYM_REF2(subrange_specification_c, integer_type_name, subrange)

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/*  signed_integer DOTDOT signed_integer */

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/* dimension will be filled in during stage 3 (array_range_check_c) with the number of elements in this subrange */

   348

SYM_REF2(subrange_c, lower_limit, upper_limit, unsigned long long int dimension;)

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/*  enumerated_type_name ':' enumerated_spec_init */

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SYM_REF2(enumerated_type_declaration_c, enumerated_type_name, enumerated_spec_init)

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/* enumerated_specification ASSIGN enumerated_value */

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SYM_REF2(enumerated_spec_init_c, enumerated_specification, enumerated_value)

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/* helper symbol for enumerated_specification->enumerated_spec_init */

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/* enumerated_value_list ',' enumerated_value */

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SYM_LIST(enumerated_value_list_c)

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/* enumerated_type_name '#' identifier */

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SYM_REF2(enumerated_value_c, type, value)

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/*  identifier ':' array_spec_init */

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SYM_REF2(array_type_declaration_c, identifier, array_spec_init)

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/* array_specification [ASSIGN array_initialization] */

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/* array_initialization may be NULL ! */

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SYM_REF2(array_spec_init_c, array_specification, array_initialization)

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/* ARRAY '[' array_subrange_list ']' OF non_generic_type_name */

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SYM_REF2(array_specification_c, array_subrange_list, non_generic_type_name)

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/* helper symbol for array_specification */

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/* array_subrange_list ',' subrange */

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SYM_LIST(array_subrange_list_c)

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/* array_initialization:  '[' array_initial_elements_list ']' */

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/* helper symbol for array_initialization */

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/* array_initial_elements_list ',' array_initial_elements */

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SYM_LIST(array_initial_elements_list_c)

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   382

/* integer '(' [array_initial_element] ')' */

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/* array_initial_element may be NULL ! */

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SYM_REF2(array_initial_elements_c, integer, array_initial_element)

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/*  structure_type_name ':' structure_specification */

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SYM_REF2(structure_type_declaration_c, structure_type_name, structure_specification)

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   389

/* structure_type_name ASSIGN structure_initialization */

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/* structure_initialization may be NULL ! */

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SYM_REF2(initialized_structure_c, structure_type_name, structure_initialization)

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   393

/* helper symbol for structure_declaration */

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/* structure_declaration:  STRUCT structure_element_declaration_list END_STRUCT */

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/* structure_element_declaration_list structure_element_declaration ';' */

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SYM_LIST(structure_element_declaration_list_c)

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   398

/*  structure_element_name ':' *_spec_init */

   399

SYM_REF2(structure_element_declaration_c, structure_element_name, spec_init)

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   401

/* helper symbol for structure_initialization */

   402

/* structure_initialization: '(' structure_element_initialization_list ')' */

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/* structure_element_initialization_list ',' structure_element_initialization */

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SYM_LIST(structure_element_initialization_list_c)

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/*  structure_element_name ASSIGN value */

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SYM_REF2(structure_element_initialization_c, structure_element_name, value)

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   409

/*  string_type_name ':' elementary_string_type_name string_type_declaration_size string_type_declaration_init */

   410

/*

   411

 * NOTE:

   412

 * (Summary: Contrary to what is expected, the

   413

 *           string_type_declaration_c is not used to store

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 *           simple string type declarations that do not include

   415

 *           size limits.

   416

 *           For e.g.:

   417

 *             str1_type: STRING := "hello!"

   418

 *           will be stored in a simple_type_declaration_c

   419

 *           instead of a string_type_declaration_c.

   420

 *           The following:

   421

 *             str2_type: STRING [64] := "hello!"

   422

 *           will be stored in a sring_type_declaration_c

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 *

   424

 *           Read on for why this is done...

   425

 * End Summary)

   426

 *

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 * According to the spec, the valid construct

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 * TYPE new_str_type : STRING := "hello!"; END_TYPE

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 * has two possible routes to type_declaration...

   430

 *

   431

 * Route 1:

   432

 * type_declaration: single_element_type_declaration

   433

 * single_element_type_declaration: simple_type_declaration

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 * simple_type_declaration: identifier ':' simple_spec_init

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 * simple_spec_init: simple_specification ASSIGN constant

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 * (shift:  identifier <- 'new_str_type')

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 * simple_specification: elementary_type_name

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 * elementary_type_name: STRING

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 * (shift: elementary_type_name <- STRING)

   440

 * (reduce: simple_specification <- elementary_type_name)

   441

 * (shift: constant <- "hello!")

   442

 * (reduce: simple_spec_init: simple_specification ASSIGN constant)

   443

 * (reduce: ...)

   444

 *

   445

 *

   446

 * Route 2:

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 * type_declaration: string_type_declaration

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 * string_type_declaration: identifier ':' elementary_string_type_name string_type_declaration_size string_type_declaration_init

   449

 * (shift:  identifier <- 'new_str_type')

   450

 * elementary_string_type_name: STRING

   451

 * (shift: elementary_string_type_name <- STRING)

   452

 * (shift: string_type_declaration_size <-  empty )

   453

 * string_type_declaration_init: ASSIGN character_string

   454

 * (shift: character_string <- "hello!")

   455

 * (reduce: string_type_declaration_init <- ASSIGN character_string)

   456

 * (reduce: string_type_declaration <- identifier ':' elementary_string_type_name string_type_declaration_size string_type_declaration_init )

   457

 * (reduce: type_declaration <- string_type_declaration)

   458

 *

   459

 *

   460

 * At first glance it seems that removing route 1 would make

   461

 * the most sense. Unfortunately the construct 'simple_spec_init'

   462

 * shows up multiple times in other rules, so changing this construct

   463

 * would also mean changing all the rules in which it appears.

   464

 * I (Mario) therefore chose to remove route 2 instead. This means

   465

 * that the above declaration gets stored in a

   466

 * simple_type_declaration_c, and not in a string_type_declaration_c

   467

 * as would be expected!

   468

 */

   469

/*  string_type_name ':' elementary_string_type_name string_type_declaration_size string_type_declaration_init */

   470

SYM_REF4(string_type_declaration_c,	string_type_name,

   471

					elementary_string_type_name,

   472

					string_type_declaration_size,

   473

					string_type_declaration_init) /* may be == NULL! */

   474

   475

   476

/* helper symbol for fb_name_decl_c */

   477

/* This symbol/leaf does not exist in the IEC standard syntax as an isolated symbol,

   478

 * as, for some reason, the standard syntax defines FB variable declarations in a slightly 

   479

 * different style as all other spec_init declarations. I.e., fr FBs variable declarations, 

   480

 * the standard defines a single leaf/node (fb_name_decl) that references:

   481

 *   a) the variable name list

   482

 *   b) the FB datatype

   483

 *   c) the FB intial value

   484

 *

   485

 * All other variable declarations break this out into two nodes:

   486

 *   1) references b) and c) above (usually named ***_spec_init)

   487

 *   2) references a), and node 1)

   488

 *

   489

 * In order to allow the datatype analyses to proceed without special cases, we will handle

   490

 * FB variable declarations in the same style. For this reason, we have added the

   491

 * following node to the Abstract Syntax Tree, even though it does not have a direct equivalent in 

   492

 * the standard syntax.

   493

 */

   494

/*  function_block_type_name ASSIGN structure_initialization */

   495

/* structure_initialization -> may be NULL ! */

   496

SYM_REF2(fb_spec_init_c, function_block_type_name, structure_initialization)

   497

   498

   499

/* Taken fron IEC 61131-3 v3

   500

 * // Table 14 - Reference operations

   501

 * Ref_Type_Decl  : Ref_Type_Name ':' Ref_Spec_Init ;

   502

 * Ref_Spec_Init  : Ref_Spec ( ':=' Ref_Value )? ;

   503

 * Ref_Spec       : 'REF_TO' Non_Gen_Type_Name ;

   504

 * Ref_Type_Name  : Identifier ;

   505

 * Ref_Name       : Identifier ;

   506

 * Ref_Value      : Ref_Addr | 'NULL' ;

   507

 * Ref_Addr       : 'REF' '(' (Symbolic_Variable | FB_Name | Class_Instance_Name ) ')' ;

   508

 * Ref_Assign     : Ref_Name ':=' (Ref_Name | Ref_Deref | Ref_Value ) ;

   509

 * Ref_Deref      : 'DREF' '(' Ref_Name ')' ;

   510

 */