override object accessot javascript -

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i override accessor of javascript object instead of override should return fixed value.

eg.

var obj = {}; console.log(obj.someproperty) //will print undefined expected value false

if property undefined there no way have return false default "falsey".

for example:

var obj = {}; if (!obj.someproperty) {         console.log("expression falsey"); }

a more explicit way test truthiness use double bang operator:

var obj = {}; console.log(!!obj.someproperty) // print's undefined, evaluates false

but in short, going after not work because in javascript cannot redefine undefined.

Ben