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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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/* 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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 * preceded by a unary minus operator.

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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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SYM_REF2(numeric_literal_c, type, value)

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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_REF2(duration_c, neg, interval)

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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_REF1(time_of_day_c, daytime)

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SYM_REF3(daytime_c, day_hour, day_minute, day_second)

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SYM_REF1(date_c, date_literal)

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SYM_REF3(date_literal_c, year, month, day)

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SYM_REF2(date_and_time_c, 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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SYM_REF0(constant_int_type_name_c)

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SYM_REF0(constant_real_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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SYM_REF2(input_declarations_c, option, input_declaration_list)

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/* helper symbol for input_declarations */

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SYM_LIST(input_declaration_list_c)

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

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SYM_REF2(edge_declaration_c, edge, var1_list)

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SYM_REF0(raising_edge_option_c)

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SYM_REF0(falling_edge_option_c)

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/* spec_init is one of the following...

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 *    simple_spec_init_c *

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 *    subrange_spec_init_c *

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 *    enumerated_spec_init_c *

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 */

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SYM_REF2(var1_init_decl_c, var1_list, spec_init)

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/* | var1_list ',' variable_name */

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SYM_LIST(var1_list_c)

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/* var1_list ':' array_spec_init */

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SYM_REF2(array_var_init_decl_c, var1_list, array_spec_init)

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/*  var1_list ':' initialized_structure */

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SYM_REF2(structured_var_init_decl_c, var1_list, initialized_structure)

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/* fb_name_list ':' function_block_type_name ASSIGN structure_initialization */

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/* structure_initialization -> may be NULL ! */

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SYM_REF3(fb_name_decl_c, fb_name_list, function_block_type_name, structure_initialization)

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/* fb_name_list ',' fb_name */

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SYM_LIST(fb_name_list_c)

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/* VAR_OUTPUT [RETAIN | NON_RETAIN] var_init_decl_list END_VAR */

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/* option -> may be NULL ! */

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SYM_REF2(output_declarations_c, option, var_init_decl_list)

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/*  VAR_IN_OUT var_declaration_list END_VAR */

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SYM_REF1(input_output_declarations_c, var_declaration_list)

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/* helper symbol for input_output_declarations */

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/* var_declaration_list var_declaration ';' */

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SYM_LIST(var_declaration_list_c)

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/*  var1_list ':' array_specification */

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SYM_REF2(array_var_declaration_c, var1_list, array_specification)

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/*  var1_list ':' structure_type_name */

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SYM_REF2(structured_var_declaration_c, var1_list, structure_type_name)

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/* VAR [CONSTANT] var_init_decl_list END_VAR */

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/* option -> may be NULL ! */

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SYM_REF2(var_declarations_c, option, var_init_decl_list)

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/*  VAR RETAIN var_init_decl_list END_VAR */

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SYM_REF1(retentive_var_declarations_c, var_init_decl_list)

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/*  VAR [CONSTANT|RETAIN|NON_RETAIN] located_var_decl_list END_VAR */

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/* option -> may be NULL ! */

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SYM_REF2(located_var_declarations_c, option, located_var_decl_list)

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/* helper symbol for located_var_declarations */

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/* located_var_decl_list located_var_decl ';' */

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SYM_LIST(located_var_decl_list_c)

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/*  [variable_name] location ':' located_var_spec_init */

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/* variable_name -> may be NULL ! */

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SYM_REF3(located_var_decl_c, variable_name, location, located_var_spec_init)

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/*| VAR_EXTERNAL [CONSTANT] external_declaration_list END_VAR */

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/* option -> may be NULL ! */

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SYM_REF2(external_var_declarations_c, option, external_declaration_list)

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/* helper symbol for external_var_declarations */

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/*| external_declaration_list external_declaration';' */

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SYM_LIST(external_declaration_list_c)

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   433

/*  global_var_name ':' (simple_specification|subrange_specification|enumerated_specification|array_specification|prev_declared_structure_type_name|function_block_type_name */

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SYM_REF2(external_declaration_c, global_var_name, specification)

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   436

/*| VAR_GLOBAL [CONSTANT|RETAIN] global_var_decl_list END_VAR */

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/* option -> may be NULL ! */

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SYM_REF2(global_var_declarations_c, option, global_var_decl_list)

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/* helper symbol for global_var_declarations */

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/*| global_var_decl_list global_var_decl ';' */

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SYM_LIST(global_var_decl_list_c)

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/*| global_var_spec ':' [located_var_spec_init|function_block_type_name] */

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/* type_specification ->may be NULL ! */

   446

SYM_REF2(global_var_decl_c, global_var_spec, type_specification)

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   448

/*| global_var_name location */

   449

SYM_REF2(global_var_spec_c, global_var_name, location)

   450

   451

/*  AT direct_variable */

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SYM_REF1(location_c, direct_variable)

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   454

/*| global_var_list ',' global_var_name */

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SYM_LIST(global_var_list_c)

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   457

/*  var1_list ':' single_byte_string_spec */

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SYM_REF2(single_byte_string_var_declaration_c, var1_list, single_byte_string_spec)

   459

   460

/*  STRING ['[' integer ']'] [ASSIGN single_byte_character_string] */

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/* integer ->may be NULL ! */

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/* single_byte_character_string ->may be NULL ! */

   463

SYM_REF2(single_byte_string_spec_c, integer, single_byte_character_string)

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   465

/*  var1_list ':' double_byte_string_spec */

   466

SYM_REF2(double_byte_string_var_declaration_c, var1_list, double_byte_string_spec)

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   468

/*  WSTRING ['[' integer ']'] [ASSIGN double_byte_character_string] */

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/* integer ->may be NULL ! */

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/* double_byte_character_string ->may be NULL ! */

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SYM_REF2(double_byte_string_spec_c, integer, double_byte_character_string)

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   473

/*| VAR [RETAIN|NON_RETAIN] incompl_located_var_decl_list END_VAR */

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/* option ->may be NULL ! */

   475

SYM_REF2(incompl_located_var_declarations_c, option, incompl_located_var_decl_list)

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   477

/* helper symbol for incompl_located_var_declarations */

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/*| incompl_located_var_decl_list incompl_located_var_decl ';' */

   479

SYM_LIST(incompl_located_var_decl_list_c)

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   481

/*  variable_name incompl_location ':' var_spec */

   482

SYM_REF3(incompl_located_var_decl_c, variable_name, incompl_location, var_spec)

   483

   484

/*  AT incompl_location_token */

   485

SYM_TOKEN(incompl_location_c)

   486

   487

/* intermediate helper symbol for:

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 *  - non_retentive_var_decls

   489

 *  - output_declarations

   490

 */

   491

SYM_LIST(var_init_decl_list_c)

   492

   493

   494

   495

   496

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

   497

/* B.1.5 - Program organization units */

   498

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

   499

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

   500

/* B 1.5.1 - Functions */

   501

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

   502

SYM_REF4(function_declaration_c, derived_function_name, type_name, var_declarations_list, function_body)

   503

   504

/* intermediate helper symbol for

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 * - function_declaration

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 * - function_block_declaration

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 * - program_declaration

   508

 */

   509

SYM_LIST(var_declarations_list_c)

   510

   511

/* option -> storage method, CONSTANT or <null> */

   512

SYM_REF2(function_var_decls_c, option, decl_list)

   513

   514

/* intermediate helper symbol for function_var_decls */

   515

SYM_LIST(var2_init_decl_list_c)

   516

   517

   518

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

   519

/* B 1.5.2 - Function Blocks */

   520

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

   521

/*  FUNCTION_BLOCK derived_function_block_name io_OR_other_var_declarations function_block_body END_FUNCTION_BLOCK */

   522

SYM_REF3(function_block_declaration_c, fblock_name, var_declarations, fblock_body)

   523

   524

/* intermediate helper symbol for function_declaration */

   525

/*  { io_var_declarations | other_var_declarations }   */

   526

/*