Give TextShow{1,2} quantified superclasses
#58
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Currently, all of the `Generic`-related functionality for both `TextShow` and `TextShow1` is contained within a single set of `GTextShow*` classes. This proves troublesome when attempting to add a quantified superclass to `TextShow1`, however, because if we were to define a `TextShow` instance for `FromGeneric1 f a` (as required by the quantified superclass), then we would have to add `TextShow a` to the instance context, which is too constrained. This takes a different approach by splitting `GTextShow*` into two sets of classes: one `GTextShow*` set (specifically for generic derivation of `TextShow` functionality) and another `GTextShow1*` set (specifically for generic derivation of `TextShow1` functionality). This requires some backwards-incompatible changes to the API in `TextShow.Generic`, but this change will not affect most users of the code. This is in preparation for a subsequent commit targeting #56.
This mirrors a corresponding change to the `Show1` and `Show2` classes in `base`—see haskell/core-libraries-committee#10. A consequence of this change is that all `TextShow1` instances now require corresponding `TextShow` instances. This affects the `TextShow.Generic` module, as we now have to define a `TextShow` instance for `FromGeneric1`. Similarly, all `TextShow2` instances now require corresponding `TextShow` and `TextShow1` instances. Fixes #56.
Sigh. See #51.
This library has a habit of tickling old GHC simplifier bugs, and this time, we've hit one in 8.10. Oh well. What's a little more CPP among friends?
The `INLINE` annotations don't cause the compile times to blow up on older versions of GHC like they do on 8.10, but they do increase noticeably enough (usually a couple minutes or more on GitHub Actions CI jobs) to the point where I'm not comfortable with it. Luckily, this doesn't happen on 9.2 or later, so let's just restrict the use of `INLINE` annotations to those versions.
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This mirrors a corresponding change to the
Show1andShow2classes inbase—see haskell/core-libraries-committee#10. A consequence of this change is that allTextShow1instances now require correspondingTextShowinstances. This affects theTextShow.Genericmodule, as we now have to define aTextShowinstance forFromGeneric1. Similarly, allTextShow2instances now require correspondingTextShowandTextShow1instances.Fixes #56.