(bison.info) Grammar Layout

Info Catalog

(bison.info) Stages

(bison.info) Concepts

 
 The Overall Layout of a Bison Grammar
 =====================================
 
    The input file for the Bison utility is a "Bison grammar file".  The
 general form of a Bison grammar file is as follows:
 
      %{
      C DECLARATIONS
      %}
      
      BISON DECLARATIONS
      
      %%
      GRAMMAR RULES
      %%
      ADDITIONAL C CODE
 
 The `%%', `%{' and `%}' are punctuation that appears in every Bison
 grammar file to separate the sections.
 
    The C declarations may define types and variables used in the
 actions.  You can also use preprocessor commands to define macros used
 there, and use `#include' to include header files that do any of these
 things.
 
    The Bison declarations declare the names of the terminal and
 nonterminal symbols, and may also describe operator precedence and the
 data types of semantic values of various symbols.
 
    The grammar rules define how to construct each nonterminal symbol
 from its parts.
 
    The additional C code can contain any C code you want to use.  Often
 the definition of the lexical analyzer `yylex' goes here, plus
 subroutines called by the actions in the grammar rules.  In a simple
 program, all the rest of the program can go here.
 

Info Catalog

(bison.info) Stages

(bison.info) Concepts