Are there pointers in javascript?

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No, JS doesn’t have pointers.

Objects are passed around by passing a copy of a reference. The programmer cannot access any C-like “value” representing the address of an object.

Within a function, one may change the contents of a passed object via that reference, but you cannot modify the reference that the caller had because your reference is only a copy:

var foo = {'bar': 1};

function tryToMungeReference(obj) {
    obj = {'bar': 2};  // won't change caller's object
}

function mungeContents(obj) {
    obj.bar = 2;       // changes _contents_ of caller's object
}

tryToMungeReference(foo);
foo.bar === 1;   // true - foo still references original object

mungeContents(foo);
foo.bar === 2;  // true - object referenced by foo has been modified

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