Skip to content
This repository has been archived by the owner on Jul 24, 2024. It is now read-only.

[Merged by Bors] - refactor(set_theory/game/nim): 0 ≈ nim 0nim 0 ≈ 0 #14270

Closed
wants to merge 3 commits into from

Conversation

vihdzp
Copy link
Collaborator

@vihdzp vihdzp commented May 20, 2022

We invert the directions of a few simple equivalences/relabellings to a more natural order (simpler on the RHS).


Open in Gitpod

@vihdzp vihdzp added easy < 20s of review time. See the lifecycle page for guidelines. awaiting-review The author would like community review of the PR labels May 20, 2022
end

@[simp] theorem nim_one_equiv : star ≈ nim 1 := nim_one_relabelling.equiv
@[simp] theorem star_equiv_nim : star ≈ nim 1 := star_relabelling_nim.equiv

@[simp] lemma nim_birthday (O : ordinal) : (nim O).birthday = O :=
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Note that if we flip the above we should ensure we have a simp lemma that says star.birthday = 1.

Copy link
Collaborator Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

We don't currently have said lemma, but I believe it would rather belong as a basic lemma on birthday.lean.

Copy link
Collaborator Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

@kim-em kim-em removed the easy < 20s of review time. See the lifecycle page for guidelines. label May 22, 2022
@kim-em
Copy link
Collaborator

kim-em commented May 22, 2022

bors merge

@github-actions github-actions bot added ready-to-merge All that is left is for bors to build and merge this PR. (Remember you need to say `bors r+`.) and removed awaiting-review The author would like community review of the PR labels May 22, 2022
bors bot pushed a commit that referenced this pull request May 22, 2022
We invert the directions of a few simple equivalences/relabellings to a more natural order (simpler on the RHS).
@bors
Copy link

bors bot commented May 23, 2022

Pull request successfully merged into master.

Build succeeded:

@bors bors bot changed the title refactor(set_theory/game/nim): 0 ≈ nim 0nim 0 ≈ 0 [Merged by Bors] - refactor(set_theory/game/nim): 0 ≈ nim 0nim 0 ≈ 0 May 23, 2022
@bors bors bot closed this May 23, 2022
@bors bors bot deleted the nim_zero_equiv branch May 23, 2022 01:49
Sign up for free to subscribe to this conversation on GitHub. Already have an account? Sign in.
Labels
ready-to-merge All that is left is for bors to build and merge this PR. (Remember you need to say `bors r+`.)
Projects
None yet
Development

Successfully merging this pull request may close these issues.

3 participants