debugging - Check if object exists in JavaScript -

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how verify existence of object in javascript?

the following works:

if (!null)    alert("got here");

but fails:

if (!maybeobject)    alert("got here");

error: maybeobject not defined.

you can safely use typeof operator on undefined variables.

if has been assigned value, including null, typeof return other undefined. typeof returns string.

therefore

if (typeof maybeobject != "undefined") {    alert("got there"); }

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