break while; break for; break foreach

[Steven Schveighoffer]

On 5/14/21 10:17 AM, Steven Schveighoffer wrote:
> On 5/13/21 4:14 PM, sighoya wrote:
>> On Thursday, 13 May 2021 at 19:36:28 UTC, Steven Schveighoffer wrote:
>>> The problem I've had with it is that a label cannot be repeated 
>>> within a function, so it's hard to write generic code which requires 
>>> this feature.
>>
>> Can't this be relaxed in some way?
>>
> 
> I'm not sure how. If you were not able to jump into scopes, then it 
> might make sense to allow multiple labels of the same name.
> 
> Besides, this doesn't fix the issues that you brought up. If you have 
> multiple labels, named the same thing, how do you decide which one to go 
> to?

Hm... possibly another solution, is to attribute the label as "scope 
only", that is, it's only valid within the scope it's declared in. This 
is kind of similar to how case labels work.

Like:

```d
static foreach(...) {
{ // note extra scope needed
    scope loop:
    foreach(...) {
        switch(...) {
            break loop;
        }
    }
}}

// goto loop; // would be an error
```

This actually might be more powerful than just breaking out of a given 
loop, because it would enable other label statements like `goto`, and 
also allows dealing with nested loops.

-Steve