[javascript] javascript, for loop defines a dynamic variable name

Folks, Not sure if eval() or window() is the answer, but I am trying to loop through an array, and create variables for each item in that array dynamically.

My myArray looks like:



for (var i = myArray.length - 1; i >= 0; i--) {    var myVar = eval(myArray[i]) };  console.log(foo) console.log(bar) console.log(baz) 

Is this possible?

This question is related to javascript

The answer is

I think you could do it by creating parameters in an object maybe?

var myObject = {}; for(var i=0;i<myArray.length;i++) {     myObject[ myArray[i] ]; } 

If you don't set them to anything, you'll just have an object with some parameters that are undefined. I'd have to write this myself to be sure though.

You cannot create different "variable names" but you can create different object properties. There are many ways to do whatever it is you're actually trying to accomplish. In your case I would just do

for (var i = myArray.length - 1; i >= 0; i--) {    console.log(eval(myArray[i])); }; 

More generally you can create object properties dynamically, which is the type of flexibility you're thinking of.

var result = {}; for (var i = myArray.length - 1; i >= 0; i--) {     result[myArray[i]] = eval(myArray[i]);   }; 

I'm being a little handwavey since I don't actually understand language theory, but in pure Javascript (including Node) references (i.e. variable names) are happening at a higher level than at runtime. More like at the call stack; you certainly can't manufacture them in your code like you produce objects or arrays. Browsers do actually let you do this anyway though it's terrible practice, via

window['myVarName'] = 'namingCollisionsAreFun';  

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