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/*

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 * (c) 2003 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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/* Decomposes a variable instance name into its constituents,

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 * example:

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 *    window.points[1].coordinate.x

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 *

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 *  will succesfully return

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 *        - window

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 *        - points

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 *        - coordinate

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 *        - x

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 * on succesive calls to decompose_var_instance_name_c::next_part()

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 */

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#include "../absyntax/visitor.hh"

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class decompose_var_instance_name_c: null_visitor_c {

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  private:

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    symbol_c *variable_name;

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    symbol_c *next_variable_name;

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    symbol_c *current_recursive_variable_name;

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    symbol_c *previously_returned_variable_name;

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  public:

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    decompose_var_instance_name_c(symbol_c *variable_instance_name);

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    symbol_c *next_part(void);

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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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    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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    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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    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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  /*  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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}; // decompose_var_instance_name_c

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