[Merged by Bors] - doc(RingTheory/LaurentSeries): correct docstring

[AntoineChambert-Loir]

Remove a superfluous backtick and remove .symm in a lemma of the docstring so that it can be made clickable.

---

[github-actions]

PR summary 5c8ca5c322

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference

---

Declarations diff

No declarations were harmed in the making of this PR! 🐙

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.

---

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).

[faenuccio]

The map powerSeries_equiv_subring goes from K[[X]] to the Subring of K((X)), so I am not sure about your second proposal of removing symm. Is that because you consider "being isomorphic to" as an equivalence relation that is not "ordered" and so two things are isomorphic as well as through an iso f and through f.symm?

[AntoineChambert-Loir]

Exactly. One could add that this is given by the inverse of the function, but I think that it is more helpful to have the website providing the link. (Another possibility is to have the docstring-to-html translator being able to recognize this,
but that's beyond my ability.)

[faenuccio]

Exactly. One could add that this is given by the inverse of the function, but I think that it is more helpful to have the website providing the link. (Another possibility is to have the docstring-to-html translator being able to recognize this, but that's beyond my ability.)

OK, I see your point, and actually quite like it. The docstring-to-html is also beyond my ability, so I think this PR is good as it is. Thanks!

[faenuccio]

maintainer merge

[github-actions]

🚀 Pull request has been placed on the maintainer queue by faenuccio.

[riccardobrasca]

Thanks!

bors d+

[mathlib-bors]

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

[AntoineChambert-Loir]

bors r+

[mathlib-bors]

Build failed:

• Build

[AntoineChambert-Loir]

bors r+

[mathlib-bors]

Pull request successfully merged into master.

Build succeeded:

• Build
• Lint style