How to check for null and undefined variables? (JavaScript)

Using a hardcoded if...else operator like this will do the trick:

if (variable === null || variable === undefined) {

// do something else

}

But seeing the code above makes me wonder if there are any concise way to do this. Then, I stumbled upon a stackoverflow answer that answers the question in a very concise manner:

https://stackoverflow.com/questions/2647867/how-can-i-determine-if-a-variable-is-undefined-or-null

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Document Layout Analysis

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Installing Laravel in Linux Operating System

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