AI Code

JavaScript Memory efficiency

Drawback of creating true private method

One drawback of creating private method in Javascript is memory-inefficient because a copy of the private method will be created every time a new instance is created. See this simple example.

function contact(first, last) {
    this.firstName = first;
    this.lastName = last;;

    // private method
    var formatPhoneNumber = function(number) {
        // format phone number based on input

    // public method
    this.setMobileNumber = function(number) { = formatPhoneNumber(number);

When you create few instances, they all have a copy of formatPhoneNumber method

var rob = new contact('Rob', 'Sanderson');
var don = new contact('Donald', 'Trump');
var andy = new contact('Andy', 'Whitehall');

Thus, would be great to avoid using private method only if it's necessary.

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