Add algorithms: filter, map and equals

[jacob-carlborg]

Also adds function to create static arrays.

Supersedes #11586.

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[wilzbach]

I would add opSlice overloads, s.t. the ranges can be saved/copied (I see that you have already used this for built-in arrays)

[jacob-carlborg]

That looks like it's going to be a bit more complicated. As in quite a bit of extra code need to be added. I had to draw the line somewhere to minimize the code that needed to be added.

[wilzbach]

Fair enough, we can always add it when needed.

[jacob-carlborg]

Win32 on the auto-tester times out every time. The failing test in buildkite for pbackus/sumtype seems unrelated.

[wilzbach]

Buildkite should be unbroken by dlang/phobos#7611. I don't know what's the story with win32.

[wilzbach]

Great start 👍

[wilzbach]

I think this is a great start. Any other objections / opinions?

[ghost]

Yes sorry I object. This PR needs a second commit that does refactoring using the new functions. You see just at a few places.

[ghost]

prove it is required in a second commit

[ghost]

well "required" is not what I mean. what i mean is more like "these abstractions make the code more pleasant to read and easy to understand".

[jacob-carlborg]

This is not good enough https://github.com/jacob-carlborg/dmd/blob/f9d8476176adc0a04a54b74c1aad0292356fe4df/src/dmd/objc_glue.d#L1392?

[wilzbach]

prove it is required in a second commit

We're talking about the "heart of Phobos" here. There's really no need to show why lazy, non-allocating filter and map are useful for writing maintainable code. We have been talking on and off about introducing it to DMD for years.
If you need more convincing you can just open any D project on the dub registry and I bet 95% you'll find at least one of the functions used ;-)

[ghost]

This is not good enough https://github.com/jacob-carlborg/dmd/blob/f9d8476176adc0a04a54b74c1aad0292356fe4df/src/dmd/objc_glue.d#L1392?

Why not start using it directly in dmd ? as far as i understand the example is in the fork modified for visual-d.

[jacob-carlborg]

Why not start using it directly in dmd

Because as a good citizen I split up my changes into multiple PRs to make them more manageable. 9 of my last 10 merged PRs have been all refactorings and preparations for adding support for Objective-C protocols. This one is that as well. If you insist, I know of an existing place that could benefit, but that would require walkLength as well.

as far as i understand the example is in the fork modified for visual-d

No, it definitely is not. I don't work at or use visual-d at all. If you haven't noticed, I use Mac 😉.

[ghost]

Indeed and sorry. Rainers S does, not you.

[jacob-carlborg]

Indeed and sorry. Rainers S does, not you.

No worries 😃.

[jacob-carlborg]

Thanks.

[nordlow]

BTW: for more array only overloads (non-template bloated) of Phobos algorithms see my nxt.array_algorithm here and here.