Constructor return type

[jackhl]

Constructors should use instancetype instead of id as their return type because methods that do not begin with one of the checked keywords (alloc, init, new, etc) will not get the same stricter type checking.

See http://clang.llvm.org/docs/LanguageExtensions.html#objc_instancetype

[jspahrsummers]

Can you please add a space before this bullet, and a blank line after it? Otherwise, the "Expressions" section gets indented as if part of this line item.

[jspahrsummers]

Mostly 👍, but it's worth noting that instancetype isn't always appropriate. For example, a constructor added to NSValue probably shouldn't be instancetype, because that would imply that invoking it against NSNumber would return one (when it's probably intended to just return NSValue *).

Maybe it'd be worth adding a "generally" or something to the sentence to indicate that there might be exceptions.

[jackhl]

Good point. Fixed in 5306962.

[jspahrsummers]

Thanks! ⚡