기본 구조

function parameterDecorator(
	target: any,
	methodName: string,
	paramIndex: number
) {...}

function parameterDecoratorFactory(...) {
	return function(
		target: any,
		methodName: string,
		paramIndex: number
	) {...}
}

target, methodName, paramIndex

• target
• methodName
• paramIndex

Parameter Decorator Example1

2woongjae/ts-basic-decorators

function parameterDecorator(
	target: any,
	methodName: string,
	paramIndex: number
) {
	console.log('parameterDecorator start');
  console.log(target);
  console.log(methodName);
  console.log(paramIndex);
  console.log('parameterDecorator end');
}

class Test7 {
	private _name: string;
	private _age: number;

	constructor(name: string, @parameterDecorator age: number) {
		this._name = name;
		this._age = age;
	}

	print(@parameterDecorator message: string) {
		console.log(message);
	}
}

// parameterDecorator start
// Test7 { print: [Function] }
// print
// 0
// parameterDecorator end
// parameterDecorator start
// [Function: Test7]
// undefined
// 1
// parameterDecorator end