Thanks to DMD 2.112.0, my library `collections-d` is now broken,
any attempt at fixing it is futile thanks to `@system` functions
being able to call `@safe` functions, so the compiler is
immediately crashing out the moment there's an `@system` level
function. I had to completely ditch the `@trusted` ones
Is there some other way to implement a tree traversal, that
preferably works with `foreach` or at least somewhat easy to use?
I often have to rely on binary trees, both in garbage collected
threads and low-level/low-latency ones, in the latter "just let
the GC do its thing!" does not work well. "Building an array from
the tree" (as some suggested) also not really a good idea, given
that I'd have to constantly allocate a new array. Adding a root
pointer to each node is not ideal either, but might be a less bad
idea, than letting go of low-latency threads.
BTW, due to the whole attribute hell issue, every time I need a
collection, I have to do something like this, just to make sure I
don't have every foreach loop as `@system`, impure, potentially
throwing, and GC allocating regardless of the content of the
foreach loop:
```d
string makeFunc(string attr) {
import std.array : replace;
return replace(q"{
int opApply(scope int delegate(ref E) #attr dg) #attr {
if(left !is null)
if(int r = left.opApply(dg))
return r;
if(int r = dg(elem))
return r;
if(right !is null)
if(int r = right.opApply(dg))
return r;
return 0;
}
int opApply(scope int delegate(K, ref E) #attr dg) #attr {
if(left !is null)
if(int r = left.opApply(dg))
return r;
if(int r = dg(key, elem))
return r;
if(right !is null)
if(int r = right.opApply(dg))
return r;
return 0;
}
int opApplyReverse(scope int delegate(ref E) #attr dg) #attr {
if(right !is null)
if(int r = right.opApplyReverse(dg))
return r;
if(int r = dg(elem))
return r;
if(left !is null)
if(int r = left.opApplyReverse(dg))
return r;
return 0;
}
int opApplyReverse(scope int delegate(K, ref E) #attr dg) #attr
{
if(right !is null)
if(int r = right.opApplyReverse(dg))
return r;
if(int r = dg(key, elem))
return r;
if(left !is null)
if(int r = left.opApplyReverse(dg))
return r;
return 0;
}
}", "#attr", attr);
}
```
This is then used in a `mixin` to generate the required
overloads, where `attr` means the attributes I need for the
overload.
Someone really needs to write a DIP for it...
