def p_expression_plus(self, p):
        'expression : expression PLUS expression'
        p[0] = Plus(p[1], p[3], lineno=p.lineno(1))
        p.set_lineno(0, p.lineno(1))
def p_expression_plus ( self , p ) : p [ 0 ] = Plus ( p [ 1 ] , p [ 3 ] , lineno = p . lineno ( 1 ) ) p . set_lineno ( 0 , p . lineno ( 1 ) )
expression : expression PLUS expression