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