lib/Doctrine/Common/Lexer/AbstractLexer.php
public function peek()
    {
        if (isset($this->tokens[$this->position + $this->peek])) {
            return $this->tokens[$this->position + $this->peek++];
        } else {
            return null;
        }
    }
public function peek()
    {
        if (isset($this->tokens[$this->position + $this->peek])) {
            return $this->tokens[$this->position + $this->peek++];
        } else {
            return null;
        }
    }
Moves the lookahead token forward.

@return array|null The next token or NULL if there are no more tokens ahead.