Surprising outcome when null is compared to null

I'm facing a puzzling issue that I can't seem to figure out. I'm attempting to verify if a variable is null in my React Native application, but the results are not as expected. Here is the console.log snippet illustrating my problem:

    console.log(
        this.props.until,
        this.props.until != null,
        this.props.until !== null,
        !this.props.until,
        !!this.props.until);

Here's what it outputs:

[null, true, true, false, true]

How is it possible for the variable to be null, yet not equal to null when compared? It has left me questioning my understanding of TypeScript.

I appreciate any insight or help you can provide on this matter. Thank you!

Answer №1

The snippet you provided contains an error, as null != null and null !== null will always result in false.

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