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/*

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 *

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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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 *

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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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/* Determine the data type of a variable.

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 * The variable may be a simple variable, a function block instance, a

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 * struture element within a data structured type (a struct or a fb), or

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 * an array element.

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 * A mixture of array element of a structure element of a structure element

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 * of a .... is also suported!

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 *

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 * A reference to the relevant base type __definition__ is returned.

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 * This means that if we find that the variable is of type MY_INT,

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 * which was previously declared to be

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 * TYPE MY_INT: INT := 9;

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 * this class wil return INT, and __not__ MY_INT !!

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 *

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 *

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 *  example:

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 *    window.points[1].coordinate.x

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 *    window.points[1].colour

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 *    etc... ARE ALLOWED!

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 *

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 * This class must be passed the scope within which the

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 * variable was declared, and the variable name...

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 */

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class search_varfb_instance_type_c: public search_base_type_c {

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  private:

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    search_var_instance_decl_c search_var_instance_decl;

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    decompose_var_instance_name_c *decompose_var_instance_name;

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    symbol_c *current_structelement_name;

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    symbol_c *current_rawtype;

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    bool is_complex;

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  public:

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    search_varfb_instance_type_c(symbol_c *search_scope);

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    symbol_c *get_type(symbol_c *variable_name);

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    symbol_c *get_rawtype(symbol_c *variable_name);

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    unsigned int get_vartype(symbol_c *variable_name);

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    bool type_is_complex(void);

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  private:

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    /* a helper function... */

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    void *visit_list(list_c *list);

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    /* a helper function... */

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    void *base_type(symbol_c *symbol);

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  private:

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    /* We override the base class' visitor to identifier_c.

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     * This is so because the base class does not consider a function block

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     * to be a type, unlike this class that allows a variable instance

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     * of a function block type...

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     */

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    void *visit(identifier_c *type_name);

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

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    /* B 1.3.3 - Derived data types */

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

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    /*  identifier ':' array_spec_init */

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    void *visit(array_type_declaration_c *symbol);

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    /* array_specification [ASSIGN array_initialization} */

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    /* array_initialization may be NULL ! */

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    void *visit(array_spec_init_c *symbol);

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    /* ARRAY '[' array_subrange_list ']' OF non_generic_type_name */

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    void *visit(array_specification_c *symbol);

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    /*  structure_type_name ':' structure_specification */

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    void *visit(structure_type_declaration_c *symbol);

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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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    void *visit(initialized_structure_c *symbol);

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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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    void *visit(structure_element_declaration_list_c *symbol);

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    /*  structure_element_name ':' spec_init */

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    void *visit(structure_element_declaration_c *symbol);

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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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    void *visit(structure_element_initialization_list_c *symbol); /* should never get called... */

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    /*  structure_element_name ASSIGN value */

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    void *visit(structure_element_initialization_c *symbol); /* should never get called... */

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

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    /* B.1.5 - Program organization units */

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

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

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    /* B 1.5.2 - Function Blocks */

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

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    /*  FUNCTION_BLOCK derived_function_block_name io_OR_other_var_declarations function_block_body END_FUNCTION_BLOCK */

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    // SYM_REF4(function_block_declaration_c, fblock_name, var_declarations, fblock_body, unused)

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    void *visit(function_block_declaration_c *symbol);

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}; // search_varfb_instance_type_c

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