reference variable in object literal?

Question

say I have

myfunc({
  var1: 1,
  var2: 2,
})

if i want to have a value that makes use of the current unnamed object, how would I do this?

eg if I wanted

myfunc({
  var1: 1,
  var2: 2,
  var3: this.var1 + this.var2
})

obviously this does not work.

What would the correct syntax be?

score 20 · Answer 1 · answered Feb 01 '11 at 04:51

20

You could make var3 a function, and calling it will allow you to use 'this':

x= {
    v1:4,
    v2:5,
    v3:function(){return this.v1 + this.v2;}
};

alert(x.v3());

answered Feb 01 '11 at 04:51

david

17,925
4
43
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3

Exactly what the OP wanted I think. – Nathan Feb 12 '11 at 00:22
3

The problem is that syntax is different x.v1 and x.v3(). – IvanH Nov 15 '12 at 14:10
If you want the same syntax you can change v1 and v2 to be functions as well – Mesco Jun 15 '18 at 11:25

score 6 · Accepted Answer · answered Feb 01 '11 at 04:42

Unfortunately, that isn't possible. While an object literal is being constructed, no external reference to that object exists until the entire literal is evaluated. The only way to use this at this stage is to use a constructor instead:

function MyObject() {
  this.var1 = 1;
  this.var2 = 2;
  this.var3 = this.var1 + this.var2;
}

myfunc(new MyObject());

score 3 · Answer 3 · answered Feb 01 '11 at 04:42

3

You can't do it in the notation you're using. An object literal doesn't have any notion of itself in this context.

answered Feb 01 '11 at 04:42

coreyward

77,547
20
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166

reference variable in object literal?

3 Answers3

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