Pretty-printing D arrays with Mir

[jmh530]

On Monday, 1 June 2020 at 19:51:34 UTC, tastyminerals wrote:
> [snip]
>
> I see. It depends on how much work is needed for any of the 
> options, right?
>
> For now, I think having a function that does the job suffices 
> for me at least. Since I always printed tensors in Python to 
> see what's going on, I was lacking the same functionality in 
> Mir.
> I don't code in D on a daily basis but still try to learn by 
> doing small stuff. I think the current implementation is far 
> from being included into anything without rigorous code review 
> but would be glad to see better slice formatting in Mir.

Yeah, mir is kind of bare bones for some stuff.

I had meant to include the link before
https://github.com/libmir/numir/pull/10
If you look at some of the unittests you can see how it's 
different. I separated out the different tensors with extra lines 
between them, which isn't as easy to read. However, I think 
bigger than a 3-d tensor is relatively uncommon. It might be some 
work to get it to work since all the functions would need to be 
re-written to take into account the mir's new format facilities, 
but I probably wouldn't have to change the unittests too much.

I just tried to use the mir.format for the first time (code 
below). The documentation is a bit lacking at this point. The 
`print` function is like `put` function for an output range but 
with some additional functionality I don't understand yet. I 
think for it to be used completely in a @nogc manner, you would 
need a @nogc `writeln` function as well.

/+dub.sdl:
dependency "mir-algorithm" version="*"
+/
import mir.format;
import mir.appender: ScopedBuffer;
import std.stdio: writeln;

void main() {
     FormatSpec formatSpec;
     formatSpec.format = 'f';
     formatSpec.precision = 3;

     auto x = withFormat(1.5f, formatSpec);
     ScopedBuffer!char w;
     w.print(x);
     w.data.writeln;
}