[Merged by Bors] - refactor: redefine Subrel in terms of α → Prop instead of Set α

[vihdzp]

Currently, Subrel r {x | p x} interacts poorly with simp, as the type signature is rewritten from ↑{x | p x} → ↑{x | p x} → Prop to {x // p x} → {x // p x} → Prop. This can be avoided by writing Subrel r p instead.

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• depends on: [Merged by Bors] - chore(SetTheory/Ordinal/Basic): {x // x < y} → Iio y #20413

[github-actions]

PR summary 0a0294252c

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference

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Declarations diff

+ instance (r : α → α → Prop) [IsAsymm α r] (p : α → Prop) : IsAsymm _ (Subrel r p)
+ instance (r : α → α → Prop) [IsIrrefl α r] (p : α → Prop) : IsIrrefl _ (Subrel r p)
+ instance (r : α → α → Prop) [IsRefl α r] (p : α → Prop) : IsRefl _ (Subrel r p)
+ instance (r : α → α → Prop) [IsSymm α r] (p : α → Prop) : IsSymm _ (Subrel r p)
+ instance (r : α → α → Prop) [IsTrans α r] (p : α → Prop) : IsTrans _ (Subrel r p)
+ instance (r : α → α → Prop) [IsWellOrder α r] (p : α → Prop) : IsWellOrder _ (Subrel r p)
- instance (r : α → α → Prop) (p : α → Prop) [IsWellOrder α r] :
- instance (r : α → α → Prop) [IsAsymm α r] (p : Set α) : IsAsymm p (Subrel r p)
- instance (r : α → α → Prop) [IsIrrefl α r] (p : Set α) : IsIrrefl p (Subrel r p)
- instance (r : α → α → Prop) [IsRefl α r] (p : Set α) : IsRefl p (Subrel r p)
- instance (r : α → α → Prop) [IsSymm α r] (p : Set α) : IsSymm p (Subrel r p)
- instance (r : α → α → Prop) [IsTrans α r] (p : Set α) : IsTrans p (Subrel r p)
- instance (r : α → α → Prop) [IsWellOrder α r] (p : Set α) : IsWellOrder p (Subrel r p)
-++- codRestrict

You can run this locally as follows

## summary with just the declaration names:
./scripts/declarations_diff.sh <optional_commit>

## more verbose report:
./scripts/declarations_diff.sh long <optional_commit>

The doc-module for script/declarations_diff.sh contains some details about this script.

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No changes to technical debt.

You can run this locally as

./scripts/technical-debt-metrics.sh pr_summary

• The relative value is the weighted sum of the differences with weight given by the inverse of the current value of the statistic.
• The absolute value is the relative value divided by the total sum of the inverses of the current values (i.e. the weighted average of the differences).

[mathlib4-dependent-issues-bot]

This PR/issue depends on:

• [Merged by Bors] - chore(SetTheory/Ordinal/Basic): {x // x < y} → Iio y #20413
  By Dependent Issues (🤖). Happy coding!

[b-mehta]

bors d+

[mathlib-bors]

✌️ vihdzp can now approve this pull request. To approve and merge a pull request, simply reply with bors r+. More detailed instructions are available here.

[leanprover-community-mathlib4-bot]

As this PR is labelled auto-merge-after-CI, we are now sending it to bors:

bors merge

[mathlib-bors]

👎 Rejected by label

[vihdzp]

bors r+

[mathlib-bors]

Pull request successfully merged into master.

Build succeeded:

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