Bolts 0.4 meta programming library

[John Colvin]

On Thursday, 2 August 2018 at 07:47:19 UTC, aliak wrote:
> Hi, just a release of a meta programming library 
> (https://bolts.dub.pm) that has utilities that I use in 
> personal projects, and that I find in phobos, and or in the 
> forums. A notable difference is that functions here try to 
> operate on any compile time entities if they can be resolved.
>
> I.e.:
>
> int i;
> void g0(int) {}
> struct S { void g1(int) {} }
> alias g2 = (int a) => a;
> static assert(isFunctionOver!(g0, int));
> static assert(isFunctionOver!(S.g1, 3));
> static assert(isFunctionOver!(g2, i));
>
> And there's a "doth" super template that tries to contain most 
> things under what I feel is a nicer api ("is" was taken, so i 
> looked to Shakespearian gibberish :p) and also allows for 
> easier use with meta functions:
>
> E.g.:
>
> int *pi = null;
> static assert( doth!3.of!int);
> static assert(!doth!pi.nullable);
> static assert( doth!((a, b, c, d) => a).functionOver!(int, int, 
> int, int));
>
> int i;
> import std.meta: allSatisfy;
> static assert(allSatisfy!(doth!int.of, 3, 4, int, i));
>
> Here's an example of a gem adapted from inside the forms/phobos 
> sources as well:
>
> alias a = AliasPack!(1, 2, 3);
> alias b = AliasPack!(4, 5, 6);
> alias c = AliasPack!(7, 8, 9);
>
> alias d = staticZip!(a, b, c);
>
> static assert(d.length == 3);
>
> static assert(d.Unpack[0].equals!(1, 4, 7));
> static assert(d.Unpack[1].equals!(2, 5, 8));
> static assert(d.Unpack[2].equals!(3, 6, 9))
>
> static assert(AliasPack!(d.UnpackDeep).equals!(1, 4, 7, 2, 5, 
> 8, 3, 6, 9));
>
> Cheers,
> - Ali

This looks cool. Lots of things that lots of people have 
reimplemented lots of times over the years, but all in one place 
and documented.

2 points:

1) Are you aware of this: 
https://github.com/dlang/phobos/blob/master/std/meta.d ? I think 
if a bunch of good motivating examples are given, making this 
public would be possible. Then everyone would be using the same 
one and your library would truly just be utilities.