Add instance Ix for Unsigned and Signed.

[gergoerdi]

This allows using Signed n and Unsigned n as Data.Array indices,
for example in test benches that simulate memory.

[martijnbastiaan]

LGTM, could you add a changelog entry? See README.md at https://github.com/clash-lang/clash-compiler/tree/master/changelog.

[alex-mckenna]

Not to nitpick, but as you're not defining any of the GHC-specific unsafe Ix functions, would you also mind changing from GHC.Arr to Data.Ix?

[gergoerdi]

Not to nitpick, but as you're not defining any of the GHC-specific unsafe Ix functions, would you also mind changing from GHC.Arr to Data.Ix?

That's fair, I'll do that. But hopefully we'll get indexError back... https://gitlab.haskell.org/ghc/ghc/-/issues/18579

[gergoerdi]

Not to nitpick, but as you're not defining any of the GHC-specific unsafe Ix functions, would you also mind changing from GHC.Arr to Data.Ix?

I've done this just now.

[martijnbastiaan]

Cool! I think we can merge it after a CHANGELOG entry.

[gergoerdi]

Cool! I think we can merge it after a CHANGELOG entry.

But the git log shows that CHANGELOG is updated after-the-fact, at release time, not in individual commits.

[martijnbastiaan]

That's true, but we keep each entry as a file so we can easily backport / update the changelog later. See:

• https://github.com/clash-lang/clash-compiler/blob/master/changelog/README.md
• https://github.com/clash-lang/clash-compiler/tree/master/changelog

[gergoerdi]

That's true, but we keep each entry as a file so we can easily backport / update the changelog later.

The friction is real...

[martijnbastiaan]

The friction is real...

ikr..