`undefined`: The Third Boolean Value? css-tricks.com/undefined-the-… (It's neither `true` or `false`, and sometimes that third option might be what you really want.)

@JavaScriptDaily This is not a good idea, for many, many reasons. Don't be lazy; be explicit about your app states.

@JavaScriptDaily True, false, or... dunno.

@JavaScriptDaily Schrodinger cat of javascript. What we don't know can't be true or false or either one.