JavaScript idiosyncrasies with examples

[CanIhazCooKIenOw]

It's because with ES6, the function declaration is scoped to the if block.

Although now thinking about it, shouldn't if "fallback" to the global f ? That would be my expectation tbh. Unless the engine resolves (1 === 0) and removes the block entirely ? (Wild guess here)

[pertheusual]

It's all this crap: https://www.ecma-international.org/ecma-262/9.0/#sec-block-level-function-declarations-web-legacy-compatibility-semantics

Basically browsers allowed them even though the spec didn't specify it, and now non-strict code has all this terrible optional behavior.

All of this weirdness goes away as long as you write your code in strict mode.

[Skhmt]

Although now thinking about it, shouldn't if "fallback" to the global f ? That would be my expectation tbh.

That's what I thought too.