Node:C Code, Previous:Grammar Rules, Up:Grammar Outline
The additional C code section is copied verbatim to the end of the
parser file, just as the C declarations section is copied to the
beginning. This is the most convenient place to put anything that you
want to have in the parser file but which need not come before the
definition of yyparse
. For example, the definitions of
yylex
and yyerror
often go here. See Parser C-Language Interface.
If the last section is empty, you may omit the %%
that separates it
from the grammar rules.
The Bison parser itself contains many static variables whose names start
with yy
and many macros whose names start with YY
. It is a
good idea to avoid using any such names (except those documented in this
manual) in the additional C code section of the grammar file.