My preference from the current suggestions would be Never.

-Thorsten 

> Am 06.06.2016 um 15:24 schrieb Thorsten Seitz via swift-evolution 
> <[email protected]>:
> 
> Ceylon uses `Nothing` for the bottom type.
> 
> -Thorsten 
> 
>> Am 05.06.2016 um 20:39 schrieb Charlie Monroe via swift-evolution 
>> <[email protected]>:
>> 
>> While None is probably the best way to describe the opposite of Any, it 
>> would be often mistaken for .None (i.e. Optional) by newcomers to the 
>> language.
>> 
>> I'd personally prefer calling it "Nil" (capital N), which really means 
>> "nonexistent". The same way ObjC had "nil" for "id" and "Nil" for Class. 
>> Possibly, to avoid confusion with nil, calling it Null? Though that might 
>> get confused with NSNull, once the NS prefix gets dropped.
>> 
>> Or "Nothing" as in Scala.
>> 
>>> On Jun 5, 2016, at 8:26 PM, Антон Жилин via swift-evolution 
>>> <[email protected]> wrote:
>>> 
>>> The following names were suggested: NoReturn, Bottom, None, Never.
>>> I would pick None, because it looks like opposite to Any and fits nicely in 
>>> generic types.
>>> 
>>> I would prefer the type to be simple, and be implemented as a case-less 
>>> enum (not a bottom value, as in Haskell).
>>> 
>>> None should be a usual enum, with no compiler magic except that functions 
>>> returning None are equivalent to current @noreturn.
>>> 
>>> Example 1.
>>> let x: None?
>>> // ...
>>> let y = x!
>>> 
>>> It will trap in runtime not because we discover scary bottom thing, as in 
>>> Haskell, but because x had value Optional.none at that moment and we 
>>> asserted otherwise.
>>> We could prove that it is always true in this case, but compiler must be 
>>> stupid about this.
>>> 
>>> Example 2.
>>> Compiler should allow including None in structures. Error will show up in 
>>> constructor, when we will not be able to initialize the field.
>>> 
>>> Example 3.
>>> None in an enum case makes that case never appear in values of such a type. 
>>> But compiler can not know about that.
>>> 
>>> - Anton
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