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GNU Info (bison.info)Union DeclThe Collection of Value Types ----------------------------- The `%union' declaration specifies the entire collection of possible data types for semantic values. The keyword `%union' is followed by a pair of braces containing the same thing that goes inside a `union' in C. For example: %union { double val; symrec *tptr; } This says that the two alternative types are `double' and `symrec *'. They are given names `val' and `tptr'; these names are used in the `%token' and `%type' declarations to pick one of the types for a terminal or nonterminal symbol (Note: Nonterminal Symbols.). Note that, unlike making a `union' declaration in C, you do not write a semicolon after the closing brace. automatically generated by info2www version 1.2.2.9 |