Copy an array without linking to it

Question

var ProtVar = function(arr){
    this.gr1 = [];
    this.gr2 = [];
    this.arr = arr;
    return this;
}
ProtVar.prototype.setArrs = function(){
    this.gr1 = this.arr;
    this.gr2 = this.arr;
    return this;
}
ProtVar.prototype.shiftGr1 = function(){
    this.gr1.shift();
    return this;
}
ProtVar.prototype.showData = function(){
    console.log("gr1 = ", this.gr1.length, this.gr1);
    console.log("gr2 = ", this.gr2.length, this.gr2);
    console.log("arr = ", this.arr.length, this.arr);    
    return this;   
}
var protVar = new ProtVar([1,2,3,4]).setArrs().shiftGr1().showData();

How should I copy the array without linking to the same array?

I figured out how to do this with slice(0); see below.

ProtVar.prototype.setArrs = function(){
    this.gr1 = this.arr.slice(0);
    this.gr2 = this.arr.slice(0);
    return this;
}

Is this the right way to do it?

In this case (array of primitives) it is one viable way – Andreas May 18 '16 at 07:07 — Andreas, May 18 '16 at 07:07

score 2 · Accepted Answer · edited May 23 '17 at 12:06

2

There are at least 4 (!) principal ways to clone an array:

loop

constructor

slice / splice

concat

Please see this answer

edited May 23 '17 at 12:06

Community

1
1

answered May 18 '16 at 07:08

Charlie

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thanks, sorry for duplicate question :/ – WouldBeNerd May 18 '16 at 07:09

Copy an array without linking to it

1 Answers1