continue in labeled switch

[Nick Treleaven]

On Saturday, 5 July 2025 at 02:27:33 UTC, monkyyy wrote:
> from the 2026 update for zig he showed off labeled switches
> https://youtu.be/x3hOiOcbgeA?si=rr69iKJOZ2CyKysi
>
> ```d
> foo: switch(0){
>   case 0:
>     "hi".writeln;
>     continue foo(2);
>   case 1:
>     "bye".writeln;
>     break;
>   case 2:
>     "hello".writeln;
>     continue foo(1);
>   default: assert(0);
> }
> ```
> would print "hi","hello","bye" this is probably the majority of 
> my uses of goto

Why is that better than using `goto case 1;`, `goto case 2;`?

https://dlang.org/spec/statement.html#goto-statement

Using `continue` for this seems like unnecessary keyword meaning 
overloading, given that AIUI `continue;` still refers to loop 
statement iteration, and a labelled switch lowers to a while 
loop(!):

>  Semantically, this is equivalent to the following loop:

https://ziglang.org/documentation/master/#toc-Switching-with-Enum-Literals

So it seems using `continue;` would silently restart the labelled 
switch statement, probably causing an infinite loop (if the 
implementation matches the spec). Or probably that is/will be a 
compile error, in which case labelled switch has limitations 
versus unlabelled switch.

Also is there a `continue foo(default);`? Having `goto default;` 
is better than having to write e.g. `continue foo(3);`, because 
`case 3:` could be added later, and jumping to the default case 
may have been the intended target - updating the latter code can 
easily be forgotten, especially for a long switch statement.