GraphQL\Language\Parser::parseVariableDefinition PHP Method

    function parseVariableDefinition()
    {
        $start = $this->lexer->token;
        $var = $this->parseVariable();
        $this->expect(Token::COLON);
        $type = $this->parseTypeReference();
        return new VariableDefinitionNode(['variable' => $var, 'type' => $type, 'defaultValue' => $this->skip(Token::EQUALS) ? $this->parseValueLiteral(true) : null, 'loc' => $this->loc($start)]);
    }