Remove benchmarks sublibrary.

[phadej]

Due how cabal-install works, all components are always solved for, and this causes unnecessary dependencies.

In case of splitmix it causes a dependency loop, so splitmix cannot test itself (or it should drop dependency on vector in tests).

Move the benchmarks into separate package, or fold into the benchmarks executable.

I'm not sure why benchmarks-O2 sublibrary is public in the first place, it isn't mentioned in the changelog.

[phadej]

The previous issue is #519

One could argue that cabal-install should be fixed, and that is true; but I don't see it happening (pessimistically) ever. Sad truth is that the issue has to be worked around.

[Shimuuar]

It was added in order to make possible to write tasty-papi based benchmark. It's in unpublished package vector-bench-papi.

Looks like easiest workaround is to split benchmarks into separate package. @lehins what's your opinion?

[Shimuuar]

So public sublibrary causes problems for downstream for little gain. It causes problem with haddock (I had to upload documentation manually). And these problems are not going to be solved anytime soon. We need better workaround. I can think about 3:

1. Move benchmarks into separate package
2. Fold vector-bench-papi into vector library and protected by manual cabal flag
3. This is firmly in hack territory. Just symlink benchmarks code from vector to vector-bench-papi.

[lehins]

One could argue that cabal-install should be fixed,

Many would argue that, including me!

but I don't see it happening (pessimistically) ever

@phadej From what I know you are one of the maintainers of cabal-install. So, I would suggest you direct your efforts at finding resources to fix this issue in cabal-install for everyone, instead of wasting your efforts on pushing other libraries to work around a bug in what is the most popular build tool in Haskell that supposedly supports sublibraries. Reaching out to Haskell Foundation for support would be one such approach. Just saying.

Having test and benchamrks sublibraries is an extremly useful feature. If it is properly supported then we would be able to provide Arbitary instances and reusable tests as well as benchamrks that poeple would be able to use for their custom instances of Unbox, Vector and MVector.

[Shimuuar]

Yes working sublibraries are great. But as said in the linked issue unless someone pays for it won't happen. And if it does happen it will take year or two: time to create design, implement it, then we need to wait for reasonable penetration of new cabal version. Or else it will happen in dark indeterminate future.

So at the moment it's probably better to revert to workarounds and hacks.

[phadej]

From what I know you are one of the maintainers of cabal-install.

I'm not, and haven't been for years.

[ulysses4ever]

@lehins

phadej From what I know you are one of the maintainers of cabal-install

sorry for the offtopic, but for the current list of maintainers, please refer to https://github.com/haskell/cabal/blob/master/MAINTAINERS.md Oleg isn't there currently.