• monkyyy (45/45) Sep 23 ```d
• Kapendev (2/7) Sep 23 Please make that a DUB package.
• monkyyy (2/10) Sep 23 Only fake anime watchers dub
• Paul Backus (24/64) Sep 30 `std.range.interfaces` already does this:

monkyyy <crazymonkyyy gmail.com> writes:

```d
import std;
struct sumrange(E){
	//void* me;
	//TypeInfo meta;
	E delegate() front_;
	E front()=>front_();
	void delegate() popFront_;
	void popFront()=>popFront_();
	bool delegate() empty_;
	bool empty()=>empty_();
	void opAssign(T)(ref T t){
		//me=cast(void*)&t;
		static assert(is(typeof(t.front())==E));
		front_=cast(E delegate())&t.front;
		popFront_=cast(void delegate())&t.popFront;
		empty_=cast(bool delegate())&t.empty;
	}
}

unittest{
	sumrange!int foo;
	auto bar=iota(int(10));
	foo=bar;
	foreach(i;foo){
		i.writeln;
	}
	auto bar2=[1,2,3].map!(a=>a);
	foo=bar2;
	foreach(i;foo){
		i.writeln;
	}
	auto bar3=only(1);
	foo=bar3;
	foreach(i;foo){
		i.writeln;
	}
	//foo=iota(10.0);//Error: static assert:  `is(double == int)` is 
false
}
```

Using sumtype or choice to get ranges to actually work in dense 
metaprogramming is very very hard; this looks like it will just 
work. Id ship it. Maybe aim for `SumRange!(ForwardRange!int)`, 
`SumRange!(BidirectionalAssignable!float)` to match upstream 
style guide

Kapendev <alexandroskapretsos gmail.com> writes:

On Wednesday, 24 September 2025 at 00:12:40 UTC, monkyyy wrote:
 Using sumtype or choice to get ranges to actually work in dense 
 metaprogramming is very very hard; this looks like it will just 
 work. Id ship it. Maybe aim for `SumRange!(ForwardRange!int)`, 
 `SumRange!(BidirectionalAssignable!float)` to match upstream 
 style guide

Please make that a DUB package.

monkyyy <crazymonkyyy gmail.com> writes:

On Wednesday, 24 September 2025 at 02:15:40 UTC, Kapendev wrote:
 On Wednesday, 24 September 2025 at 00:12:40 UTC, monkyyy wrote:
 Using sumtype or choice to get ranges to actually work in 
 dense metaprogramming is very very hard; this looks like it 
 will just work. Id ship it. Maybe aim for 
 `SumRange!(ForwardRange!int)`, 
 `SumRange!(BidirectionalAssignable!float)` to match upstream 
 style guide

 Please make that a DUB package.

Only fake anime watchers dub

Paul Backus <snarwin gmail.com> writes:

On Wednesday, 24 September 2025 at 00:12:40 UTC, monkyyy wrote:
 ```d
 import std;
 struct sumrange(E){
 	//void* me;
 	//TypeInfo meta;
 	E delegate() front_;
 	E front()=>front_();
 	void delegate() popFront_;
 	void popFront()=>popFront_();
 	bool delegate() empty_;
 	bool empty()=>empty_();
 	void opAssign(T)(ref T t){
 		//me=cast(void*)&t;
 		static assert(is(typeof(t.front())==E));
 		front_=cast(E delegate())&t.front;
 		popFront_=cast(void delegate())&t.popFront;
 		empty_=cast(bool delegate())&t.empty;
 	}
 }

 unittest{
 	sumrange!int foo;
 	auto bar=iota(int(10));
 	foo=bar;
 	foreach(i;foo){
 		i.writeln;
 	}
 	auto bar2=[1,2,3].map!(a=>a);
 	foo=bar2;
 	foreach(i;foo){
 		i.writeln;
 	}
 	auto bar3=only(1);
 	foo=bar3;
 	foreach(i;foo){
 		i.writeln;
 	}
 	//foo=iota(10.0);//Error: static assert:  `is(double == int)` 
 is false
 }
 ```

`std.range.interfaces` already does this:

```d
import std.range.interfaces;
import std.range;
import std.algorithm;
import std.stdio;

void main()
{
     InputRange!int foo;

     auto bar1 = iota(10);
     foo = bar1.inputRangeObject;
     foreach (i; foo)
         writeln(i);

     auto bar2 = [1, 2, 3].map!(a => a);
     foo = bar2.inputRangeObject;
     foreach (i; foo)
         writeln(i);

     auto bar3 = only(1);
     foo = bar3.inputRangeObject;
     foreach (i; foo)
         writeln(i);
}
```