/* This scanner prints "//" comments. */
    %option reentrant stack
    %x COMMENT
    %%
    "//"                 yy_push_state( COMMENT, yyscanner);
    .|\n
    <COMMENT>\n          yy_pop_state( yyscanner );
    <COMMENT>[^\n]+      fprintf( yyout, "%s\n", yytext);
    %%
    int main ( int argc, char * argv[] )
    {
        yyscan_t scanner;

        yylex_init ( &scanner );
        yylex ( scanner );
        yylex_destroy ( scanner );
    return 0;
   }