hacks on opApply

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On Wednesday, 27 August 2025 at 20:34:22 UTC, monkyyy wrote:
> spec doesn't define this behavior as far as I can tell
>
> ```d
> import std;
> auto loop(){
> 	struct foreach_{
> 		int opApply(int delegate(int i) dg){
> 			dg(0).writeln;//1
> 			dg(1).writeln;//2
> 			dg(2).writeln;//3
> 			return 3;
> 	}}
> 	return foreach_();
> }
> unittest{
> 	a: while(true){
> 	b: foreach(i;loop()){
> 		if(i==0){break;}
> 		if(i==1){break b;}
> 		if(i==2){break a;}
> }}}
> ```

What about continue? Does it work and return a value? Going off 
what Steven said, I assume it'd be 0.

> rn I believe you could pretty reasonably overload the behavior 
> of break in a crafted opApply to make a 2d iteration
>
> it should be possible to modify ref indexs and other stateful 
> things that are tricky with pure ranges
>
> slight errors produce infinite loops tho and this is like the 
> 3rd opApply ive ever written, no idea on stable patterns