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/*

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

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 *

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 *  Copyright (C) 2012  Mario de Sousa (msousa@fe.up.pt)

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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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 *  A small helper visitor class, that will   

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 *  return the name (tokn_c *) of a variable, as it will

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 *  appear in the variable declaration.

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 */

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/*  For ex.:

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 *       VAR

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 *          A : int;

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 *          B : ARRAY [1..9] of int;

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 *          C : some_struct_t;

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 *       END_VAR

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 *

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 *          A    := 56;

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 *          B[8] := 99;

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 *          C.e  := 77;

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 *

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 *       Calling this visitor class with symbolic_variable_c instance referencing 'A' in

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 *       the line 'A := 56', will return the string "A".

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 *

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 *       Calling this visitor class with array_variable_c instance referencing 'B[8]' in

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 *       the line 'B[8] := 99', will return the string "B".

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 *

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 *       Calling this visitor class with array_variable_c instance referencing 'C.e' in

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 *       the line 'C.e := 77', will return the string "C".

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 */

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class get_var_name_c : public search_visitor_c {    

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  public:

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    get_var_name_c(void)  {};

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    ~get_var_name_c(void) {};  

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    static token_c *get_name(symbol_c *symbol);

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  private:

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    static get_var_name_c *singleton_instance_;

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  private:  

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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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    void *visit(identifier_c *symbol);

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

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    /* B 1.4 - Variables */

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

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    // SYM_REF2(symbolic_variable_c, var_name, unused)

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    void *visit(symbolic_variable_c *symbol);

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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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    // void *visit(direct_variable_c *symbol);

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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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    void *visit(array_variable_c *symbol);

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    /* subscript_list ',' subscript */

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    // SYM_LIST(subscript_list_c)

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    // void *visit(subscript_list_c *symbol);

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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 tructured 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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    void *visit(structured_variable_c *symbol);

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};

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