public function ArithmeticFactor()
{
$sign = null;
if (($isPlus = $this->_lexer->isNextToken(Lexer::T_PLUS)) || $this->_lexer->isNextToken(Lexer::T_MINUS)) {
$this->match(($isPlus) ? Lexer::T_PLUS : Lexer::T_MINUS);
$sign = $isPlus;
}
$primary = $this->ArithmeticPrimary();
// Phase 1 AST optimization: Prevent AST\ArithmeticFactor
// if only one AST\ArithmeticPrimary is defined
if ($sign === null) {
return $primary;
}
return new AST\ArithmeticFactor($primary, $sign);
}