mario@181: /*
mario@181:  * (c) 2003 Mario de Sousa
mario@181:  *
mario@181:  * Offered to the public under the terms of the GNU General Public License
mario@181:  * as published by the Free Software Foundation; either version 2 of the
mario@181:  * License, or (at your option) any later version.
mario@181:  *
mario@181:  * This program is distributed in the hope that it will be useful, but
mario@181:  * WITHOUT ANY WARRANTY; without even the implied warranty of
mario@181:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
mario@181:  * Public License for more details.
mario@181:  *
mario@181:  * This code is made available on the understanding that it will not be
mario@181:  * used in safety-critical situations without a full and competent review.
mario@181:  */
mario@181: 
mario@181: /*
mario@181:  * An IEC 61131-3 IL and ST compiler.
mario@181:  *
mario@181:  * Based on the
mario@181:  * FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10)
mario@181:  *
mario@181:  */
mario@181: 
mario@181: 
mario@181: 
mario@181: /* Decomposes a variable instance name into its constituents,
mario@181:  * example:
mario@181:  *    window.points[1].coordinate.x
mario@181:  *
mario@181:  *  will succesfully return
mario@181:  *        - window
mario@181:  *        - points
mario@181:  *        - coordinate
mario@181:  *        - x
mario@181:  * on succesive calls to decompose_var_instance_name_c::next_part()
mario@181:  */
mario@181: 
mario@181: 
mario@181: 
mario@181: #include "../absyntax/visitor.hh"
mario@181: 
mario@181: 
mario@181: 
mario@181: class decompose_var_instance_name_c: null_visitor_c {
mario@181: 
mario@181:   private:
mario@181:     symbol_c *variable_name;
mario@181:     symbol_c *next_variable_name;
mario@181:     symbol_c *current_recursive_variable_name;
mario@181:     symbol_c *previously_returned_variable_name;
mario@181: 
mario@181:   public:
mario@181:     decompose_var_instance_name_c(symbol_c *variable_instance_name);
mario@181: 
mario@181:     symbol_c *next_part(void);
mario@181: 
mario@181:   private:
ccb@202:   /*************************/
ccb@202:   /* B.1 - Common elements */
ccb@202:   /*************************/
ccb@202:   /*******************************************/
ccb@202:   /* B 1.1 - Letters, digits and identifiers */
ccb@202:   /*******************************************/
ccb@202:     void *visit(identifier_c *symbol);
ccb@202: 
mario@181:   /*********************/
mario@181:   /* B 1.4 - Variables */
mario@181:   /*********************/
mario@181:     void *visit(symbolic_variable_c *symbol);
ccb@202: 
mario@181:   /********************************************/
mario@181:   /* B.1.4.1   Directly Represented Variables */
mario@181:   /********************************************/
mario@181:     void *visit(direct_variable_c *symbol);
mario@181:   
mario@181:   /*************************************/
mario@181:   /* B.1.4.2   Multi-element Variables */
mario@181:   /*************************************/
mario@181:   /*  subscripted_variable '[' subscript_list ']' */
mario@181:   // SYM_REF2(array_variable_c, subscripted_variable, subscript_list)
mario@181:     void *visit(array_variable_c *symbol);
mario@181:   
mario@181:   /*  record_variable '.' field_selector */
mario@181:   /*  WARNING: input and/or output variables of function blocks
mario@181:    *           may be accessed as fields of a tructured variable!
mario@181:    *           Code handling a structured_variable_c must take
mario@181:    *           this into account!
mario@181:    */
mario@181:   //SYM_REF2(structured_variable_c, record_variable, field_selector)
mario@181:     void *visit(structured_variable_c *symbol);
mario@181: 
mario@181: }; // decompose_var_instance_name_c
mario@181: 
mario@181: 
mario@181: 
mario@181: