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/*

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 * (c) 2003-2007 Mario de Sousa

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 *

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 * Offered to the public under the terms of the GNU General Public License

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 * as published by the Free Software Foundation; either version 2 of the

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 * License, or (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, but

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 * WITHOUT ANY WARRANTY; without even the implied warranty of

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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General

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 * Public License for more details.

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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 IL and ST 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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/*      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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/***************************/

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/* 2.1.6 - Pragmas */

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

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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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SYM_LIST(library_c)

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

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/* B 1.2 - Constants */

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

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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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 */

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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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/* 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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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_TOKEN(fixed_point_c)

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

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

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SYM_REF3(daytime_c, day_hour, day_minute, day_second)

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SYM_REF3(date_literal_c, year, month, day)

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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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/* B.1.3.2 - Generic data types */

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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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SYM_REF2(subrange_c, lower_limit, upper_limit)

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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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/* 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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/* 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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/* 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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/*  structure_element_name ':' *_spec_init */

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SYM_REF2(structure_element_declaration_c, structure_element_name, spec_init)

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/* helper symbol for structure_initialization */

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/* 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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/*  string_type_name ':' elementary_string_type_name string_type_declaration_size string_type_declaration_init */

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/*

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 * NOTE:

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 * (Summary: Contrary to what is expected, the

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 *           string_type_declaration_c is not used to store

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 *           simple string type declarations that do not include

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 *           size limits.

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 *           For e.g.:

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 *             str1_type: STRING := "hello!"

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 *           will be stored in a simple_type_declaration_c

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 *           instead of a string_type_declaration_c.

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 *           The following:

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

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 *           will be stored in a sring_type_declaration_c

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 *

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 *           Read on for why this is done...

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 * End Summary)

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 *

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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...

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 *

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 * Route 1:

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 * type_declaration: single_element_type_declaration

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 * 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)

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 * (reduce: simple_specification <- elementary_type_name)

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

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 * (reduce: simple_spec_init: simple_specification ASSIGN constant)

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 * (reduce: ...)

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 *

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 *

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 * 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

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 * (shift:  identifier <- 'new_str_type')

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 * elementary_string_type_name: STRING

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 * (shift: elementary_string_type_name <- STRING)

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 * (shift: string_type_declaration_size <-  empty )

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 * string_type_declaration_init: ASSIGN character_string

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

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 * (reduce: string_type_declaration_init <- ASSIGN character_string)

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

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 * (reduce: type_declaration <- string_type_declaration)

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 *

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 *

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

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 * the most sense. Unfortunately the construct 'simple_spec_init'

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

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

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

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 * that the above declaration gets stored in a

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 * simple_type_declaration_c, and not in a string_type_declaration_c

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 * as would be expected!

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 */

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/*  string_type_name ':' elementary_string_type_name string_type_declaration_size string_type_declaration_init */

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SYM_REF4(string_type_declaration_c,	string_type_name,

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					elementary_string_type_name,

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					string_type_declaration_size,

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

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

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/* B 1.4 - Variables */

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

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SYM_REF1(symbolic_variable_c, var_name)

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

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/* B.1.4.1   Directly Represented Variables */

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

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SYM_TOKEN(direct_variable_c)

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

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/* B.1.4.2   Multi-element Variables */

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

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/*  subscripted_variable '[' subscript_list ']' */

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SYM_REF2(array_variable_c, subscripted_variable, subscript_list)

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/* subscript_list ',' subscript */

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SYM_LIST(subscript_list_c)

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/*  record_variable '.' field_selector */

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/*  WARNING: input and/or output variables of function blocks

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 *           may be accessed as fields of a structured variable!

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 *           Code handling a structured_variable_c must take

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 *           this into account!

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 */

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SYM_REF2(structured_variable_c, record_variable, field_selector)

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

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/* B 1.4.3 - Declaration & Initialisation */

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

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SYM_REF0(constant_option_c)

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SYM_REF0(retain_option_c)

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SYM_REF0(non_retain_option_c)

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/* option -> the RETAIN/NON_RETAIN/<NULL> directive... */

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/* NOTE: We need to implicitly define the EN and ENO function and FB parameters when the user

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 *       does not do it explicitly in the IEC 61131-3 source code. 

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 *       To be able to distinguish later on between implictly and explicitly defined

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 *       variables, we use the 'method' flag that allows us to remember

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 *       whether this declaration was in the original source code (method -> implicit_definition_c) 

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 *       or not (method -> explicit_definition_c).

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 */

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SYM_REF3(input_declarations_c, option, input_declaration_list, method)

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/* helper symbol for input_declarations */

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SYM_LIST(input_declaration_list_c)

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/* NOTE: The formal definition of the standard is erroneous, as it simply does not

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 *       consider the EN and ENO keywords!

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 *       The semantic description of the languages clearly states that these may be

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 *       used in several ways. One of them is to declare an EN input parameter, or

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 *       an ENO output parameter.

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 *       We have added the 'en_param_declaration_c' and 'eno_param_declaration_c' 

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 *       to cover for this.

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 *

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 *       We could have re-used the standard class used for all other input variables (with

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 *       an identifier set to 'EN' or 'ENO') however we may sometimes need to add this

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 *       declaration implicitly (if the user does not include it in the source

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 *       code himself), and it is good to know whether it was added implicitly or not.

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 *       So we create a new class that has a 'method' flag that allows us to remember

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 *       whether this declaration was in the original source code (method -> implicit_definition_c) 

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 *       or not (method -> explicit_definition_c).

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 */

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SYM_REF0(implicit_definition_c)

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SYM_REF0(explicit_definition_c)

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SYM_REF4(en_param_declaration_c, name, type, value, method)

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SYM_REF3(eno_param_declaration_c, name, type, method)

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/* edge -> The F_EDGE or R_EDGE directive */

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SYM_REF2(edge_declaration_c, edge, var1_list)