json - JavaScript object assignment -

how result?

{"obj1": {     "title": "title",     "data": [1,2,3] }, "obj2": {     "title": "title",     "data": [4,5,6] }, "obj3": {     "title": "title",     "data": [7,8,9] }} 

    var obj = {title:'title'}      var newobj = {};        newobj.obj1 = obj;      newobj.obj2 = obj;      newobj.obj3 = obj;        newobj.obj1.data = [];      newobj.obj1.data = [1,2,3];        newobj.obj2.data = [];      newobj.obj2.data = [4,5,6];        newobj.obj3.data = [];      newobj.obj3.data = [7,8,9];        console.log(json.stringify(newobj))

you're assigning obj newobj's properties. wouldn't assign new object properties means they're referencing obj. , when it's referenced, whenever make changes reference, other places referenced changes.

what need make copy of obj , assign newobj's proerties. ... syntax in {} creates new object obj's properties.

var obj = {title:'title'}  var newobj = {};    newobj.obj1 = { ...obj };  newobj.obj2 = { ...obj };  newobj.obj3 = { ...obj };    newobj.obj1.data = [1,2,3];  newobj.obj2.data = [4,5,6];  newobj.obj3.data = [7,8,9];    console.log(json.stringify(newobj));

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