In this lex part of a lex-yacc program what is the purpose of adding the lines
. return yytext[0];
\n return yytext[0];
This the lex part
%{
#include "y.tab.h"
%}
%%
a return A;
b return B;
. return yytext[0];
\n return yytext[0];
%%
What does it return when it encounters \n ?