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Discussion on: JavaScript: Logical operators and Boolean Values

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André Michel Andy •

Great article! Don't forget that && and || use short-circuit evaluation, useful for use cases like feature flags and set default values:

//if flag is true, then execute this function
process.env.FLAG && someFunc();

//Instead of...
const var2 = var1 ? var1 : "something";
//...use || operator
const var2 = var1 || "something";
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Banesa Guaderrama •

Hi André! Thank you for your comment. With just some lines you have provided a great input about default values.

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Guillaume F. •

Yes!

As a reminder, the logical operators work the following way with non-boolean values:

expr1 && expr2: If expr1 is truthy, returns expr2; else, returns expr1.
expr1 || expr2: If expr1 is truthy, returns expr1; else, returns expr2.