Bubble Foundry

Javascript Type Gotchas

by Peter.

typeof null // -> object
null instanceof null // -> TypeError: Can't use instanceof on a non-object.
true instanceof Boolean // -> false
true == new Boolean(true) // -> true
true === new Boolean(true) // -> false

Needless to say, this is very annoying if you’re trying to be be careful with your types and just goes to show that not everything is an object in Javascript. Come back soon for my attempt at a solution.