Truthfulness of empty arrays in Javascript… that’s not cool!

An empty array when cast to Boolean evaluates true, indicating that it is truthy.


An empty array compared to true evaluates false, indicating that it is not truthy.

[] == true
[] == false

And yet the Boolean opposite of an empty array still evaluates false, implying that the empty array is truthy.  What’s an interpreter to do?


Just some more contradictory anecdotal evidence to help drive you mad.

Boolean([]) == []
Boolean([]) == ![]
Boolean([]) == !![]
!Boolean([]) == []

Conclusion?  I’ll just bit my tongue this time.


About andyortlieb

I've been a tinkerer and a lazy ideologist since I gained my first personal computer in 1989. I have an aversion to formal education and I prefer to learn things by experimentation. That is not a brag, it has not been a particularly helpful set of traits. My primary goals are to increase my safety, pleasure and usefulness as I work to build and modify technologies that will bring those same attributes to the masses irrespective of government. This is the documentation of my attempt at that journey.
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