[TypeScript] Reflection and Decorator Metadata

var __decorate = (this && this.__decorate) || function (decorators, target, key, desc) {
    var c = arguments.length, r = c < 3 ? target : desc === null ? desc = Object.getOwnPropertyDescriptor(target, key) : desc, d;
    if (typeof Reflect === "object" && typeof Reflect.decorate === "function") r = Reflect.decorate(decorators, target, key, desc);
    else for (var i = decorators.length - 1; i >= 0; i--) if (d = decorators[i]) r = (c < 3 ? d(r) : c > 3 ? d(target, key, r) : d(target, key)) || r;
    return c > 3 && r && Object.defineProperty(target, key, r), r;
};
function addAge(age) {
    return function (targetClass) {
        return (function () {
            function class_1() {
                this.age = age;
                this.name = new targetClass().name;
            }
            return class_1;
        }());
    };
}
var Person = (function () {
    function Person() {
        this.name = "Johnn";
    }
    Person = __decorate([
        addAge(30)
    ], Person);
    return Person;
}());
var john = new Person();
console.log(john); // {name: "Johnn", age: 30}

{
    "compilerOptions": {
        "rootDir": "src",
        "module": "commonjs",
        "target": "es5",
        "noImplicitAny": false,
        "sourceMap": false,
        "outDir": "./dist",
        "noEmitOnError": true,
        "experimentalDecorators": true,
        "emitDecoratorMetadata": true
    },
    "exclude": [
        "node_modules",
        "typings/main",
        "typings/main.d.ts"
    ]
}

var Person = (function () {
    function Person() {
        this.name = "Johnn";
    }
    Person = __decorate([
        addAge(30), 
        __metadata(‘design:paramtypes‘, [])
    ], Person);
    return Person;
}());

npm install reflect-metadata crypto --save

<script>
    System.config({
        packages: {
            "dist": {
                "defaultExtension": "js",
                "main": "main"
            },
            "rxjs": {
                "defaultExtension": "js"
            }
        },
        map: {
            "lodash": "https://npmcdn.com/lodash@4.13.1",
            "rxjs": "node_modules/rxjs",
            "reflect-metadata": "node_modules/reflect-metadata/Reflect.js",
            "crypto": "node_modules/crypto/sha1.js",
        }
    });

    System.import("dist")
</script>

import ‘reflect-metadata‘;


function example(){
    return function(targetClass){
        const types = Reflect.getMetadata(‘design:paramtypes‘, targetClass);
        console.log(types);
        return targetClass
    }
}

@example()
class Person{
    constructor(name: string, age: number){

    }
}
new Person("John", 10);