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Save a few bytes when checking the existence of module

Written byPhuoc Nguyen
Created
15 Mar, 2021
Category
Trick
Tags
JavaScript
Say we are creating a library and want to export our APIs to the consumers. In order to support the CommonJS module, we use the following check:
js
if (typeof module !== 'undefined') {
module.exports = ourFunction;
}
However, it can be shorten and saved a few bytes when being minified:
js
if (typeof module < 'u') {
// ...
}
I saw that trick when looking at the Preact's source.
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Phước Nguyễn