DIP 1017--Add Bottom Type--Final Review

[Johan Engelen]

On Wednesday, 16 January 2019 at 04:20:42 UTC, aliak wrote:
> On Tuesday, 15 January 2019 at 22:44:56 UTC, Johan Engelen 
> wrote:
>> The link does not really have answers that explain the use of 
>> a bottom type in a practical imperative language, beyond that 
>> it signifies `noreturn`.
>> The question we have is whether there is a compelling use for 
>> "bottom". I'd like to see a real code use case, besides 
>> signifying `noreturn` (trivial).
>
> A very practical use case is with error code paths where you 
> end up asserting/exiting the program, something like:
>
> int f(int i) {
>     if (i) {
>         exit(0);
>     } else {
>         return 0;
>     }
> }

This is just another example of using the bottom type to signify 
`noreturn`, which is trivially done with an attribute and doesn't 
need a new type. I'd like to see _other_ practical uses of the 
bottom type.

-Johan