Why does attempting to access an undefined property not trigger an error?

I am curious to know why

var myVar = unDef;

may trigger a ReferenceError, while

var myObj = {};
var myVar = myObj.unDef;

runs smoothly? It simply returns undefined without any runtime issues. Despite both not being defined.

Answer №1

With this method, you can utilize

if (myVar.unDef)

instead of the longer and more resource-intensive approach:

if (myVar.hasOwnProperty('unDef'))

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