Open union encoding of Eon

[newhoggy]

Changelog

- description: |
    WIP Open union encoding of Eon
# uncomment types applicable to the change:
  type:
  # - feature        # introduces a new feature
  # - breaking       # the API has changed in a breaking way
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  # - bugfix         # fixes a defect
  # - test           # fixes/modifies tests
  # - maintenance    # not directly related to the code
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Context

This doesn't work.

Checklist

• Commit sequence broadly makes sense and commits have useful messages
• The change log section in the PR description has been filled in
• New tests are added if needed and existing tests are updated. These may include:
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• Self-reviewed the diff

[newhoggy]

If I remove this constraint, I get the following error:

internal/Cardano/Api/Eon/Core.hs:50:20: error:
    • You require open sum type to contain the following element:
          a
      However, given list can store elements only of the following types:
          bs
    • In the expression: Eon (relaxOpenUnion a)
      In an equation for ‘relaxEon’:
          relaxEon (Eon a) = Eon (relaxOpenUnion a)
   |
50 | relaxEon (Eon a) = Eon (relaxOpenUnion a)
   |                    ^^^^^^^^^^^^^^^^^^^^^^

I know I don't need the constraint because if a ∈ as and as ⊆ bs then it follows that a ∈ bs, but the constraints provided by world-peace library aren't able to infer this.

[newhoggy]

An concrete version of a function I ultimately want to write and I think I might need:

memberSubset :: era ∈ small -> small ⊆ large -> era ∈ large

[github-actions]

This PR is stale because it has been open 45 days with no activity.

[github-actions]

This issue was closed because it has been stalled for 60 days with no activity.