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Discussion on: More JavaScript Mistakes You May be Making

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aumayeung profile image
John Au-Yeung

This wouldn't be 100 percent reliable since 0, empty string, and NaN are also falsy.

So you would get the second choice returned in those cases as well.

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kimsean profile image
thedevkim • Edited

Yea, i guess you could just use the snippet if you wanted to check if theres really a value or not. I think it could be useful sometimes when you are getting a value from an api and you don't have access into the backend funtions, and they just throw either undefined null 0 or empty string

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fref profile image
Fredrik Fall

My view is to have undefined something only the runtime is allowed to set, while null is something I deliberately set.
This way you get a hint who messed up if the value is missing.

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aumayeung profile image
John Au-Yeung

As long as we remember the difference, I think it's OK. Also, we have to be consistent in how we use them.

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