Reputation: 2304
How do I change a JS array in place (like a Ruby "dangerous" method, e.g. with trailing !
)
Example:
If I have this:
var arr = [1, 2, 3]
How can I make this:
arr === [2, 4, 6]
(assuming I have an appropriate function for doubling numbers) in one step, without making any more variables?
Upvotes: 3
Views: 5462
Reputation: 1
Use Array.prototype.forEach()
, third parameter is this
: input array
var arr = [1, 2, 3];
arr.forEach(function(el, index, array) {
array[index] = el * 2
});
console.log(arr)
Upvotes: 5