Typescript Object property binding.

binding.ts

function BindFunc(tar:object,property:string,f:(v:any)=>void){
    var property_emit = BIND_EMITTER(property);
    if(tar.hasOwnProperty(property_emit)){
        tar[property_emit].push(f);
    }
    else{
        BindSetup(tar,property);
        tar[property_emit].push(f);
    }
}

function BindTwoWay(property:string,tar1:object,tar2:object){
    BindFunc(tar1,property,(v)=>tar2[property] =v);
    BindFunc(tar2,property,(v)=>tar1[property] =v);
}

function BIND_EMITTER(p:string){
    return '_bind_' + p;
}

function BindSetup(tar: object, property: string) {
    var property_emit = BIND_EMITTER(property);
    if(tar[property_emit] != null) return;
    tar[property_emit] = [];
    var emitter = tar[property_emit];
    var descriptor = Object.getOwnPropertyDescriptor(Object.getPrototypeOf(tar), property);
    if (descriptor != null && descriptor.set != null && descriptor.get != null) {
        var getter = descriptor.get;
        var setter = descriptor.set;
        Object.defineProperty(tar, property, {
            get: function () {
                return getter.call(this);
            },
            set: function (v: any) {
                let curv = getter.call(this);
                if(curv != v){
                    setter.call(this, v);
                    emitter.forEach(f => f(v));
                }
            }
        })
    }
    else {
        var val = tar[property];
        var property_bind = '_bind_' + property+'_p';
        tar[property_bind] = val;
        Object.defineProperty(tar, property, {
            get: function () {
                return this[property_bind];
            },
            set: function (v: any) {
                let curv = this[property_bind];
                if(curv != v){
                    this[property_bind] = v;
                    emitter.forEach(f => f(v));
                }
            }
        })
    }
}

class ClassA{
    public p:number = 10;
}

class ClassB{
    private m_p:number =10;
    public get p():number{
        return this.m_p;
    }
    public set p(v:number){
        this.m_p = v;
    }
}

var a = new ClassA();
var b = new ClassB();

BindFunc(a,'p',(v)=>{
    console.log('a:'+v);
});

BindFunc(b,'p',(v)=>{
    console.log('b:'+v);
});

a.p = 11;
b.p = 17;

BindTwoWay('p',a,b);

a.p = 15;
console.log('>b:'+b.p);
b.p = 25;
console.log('>a:'+a.p);