javascript - Shortcut for accessing member of an object [, of an object...] -

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this question has answer here:

is there short way accessing nested object without checking each parent object?

this throw exception if foo or bar undefined:

var exists = (foo.bar.value !== undefined);

i expect check function like:

var exists = object.exists(foo.bar.value);

is there build-in javascript?

use typeof

if (typeof myobject!= "undefined") {    console.log('it exists') }

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