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0 pointstobr6y ago0 comments

The `in` operator always returns a boolean, though.

0 comments

Maybe it was just done out of habit.

A bool can be expected today. But why about 10 years from now? Defensive programming isn't a bad thing. Making assumptions is why we had the Y2K mess.

mark_and_sweep6y ago

That's an unreasonable, excessive use of defensive programming.

We're not talking about an unstable API here, we're talking about an operator.

It would be just as unreasonable to "defend" your code against `1 + 1` suddenly returning a boolean rather than a number.

Raphmedia6y ago

You already know that ìn` will return either `true` or `false`. Why use `==` which will convert data instead of `===` which will test for a boolean directly?

Ignore the symbols and use the words. Which makes more sense to you?

"[My test] strictly equals true." or "[My test] loosely equals true."

wereHamster6y ago

This looks future proof to me: `if (JSON.stringify("something" in foo).match(/t/) != null) { … }`

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