The Additional C Code Section Syntax and usage of the additional C code section. Defining Language Semantics 3.5.1 Data Types of Semantic Values Specifying one data type for all semantic values. Specifying several alternative data types. An action is the semantic definition of a grammar rule. 3.5.4 Data Types of Values in Actions Specifying data types for actions to operate on.
Most actions go at the end of a rule.
This says when, why and how to use the exceptional action in the middle of a rule. Declaring terminal symbols. Operator Precedence Declaring terminals with precedence and associativity. The Collection of Value Types Declaring the set of all semantic value types. 3.6.4 Nonterminal Symbols Declaring the choice of type for a nonterminal symbol.