FazBrowse GitHub Viewer | Trending |
URL:
| Home
Tools: [Download Repo ZIP]   [Original HTTPS Page]

Remove `list.__add__` overloads. by randolf-scholz · Pull Request #14282 · python/typeshed · GitHub

  1. python
  2. typeshed

Repository navigation

Remove list.__add__ overloads. #14282

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
randolf-scholz wants to merge 2 commits into
base: main
Choose a base branch
Could not load branches
Branch not found: {{ refName }}

Are you sure you want to change the base?

Some commits from the old base branch may be removed from the timeline, and old review comments may become outdated.
from
Conversation 11 Commits 2 Checks 50 Files changed
Open

Remove list.__add__ overloads. #14282

Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
de86d71
test without __add__ overload
randolf-scholz Jun 16, 2025
0fe433a
Update stdlib/builtins.pyi
randolf-scholz Mar 8, 2026
File filter

Filter by extension

Filter by extension .pyi  (1) All 1 file type selected
Viewed files
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Unified
Split
Hide whitespace
Diff view
Unified
Split
Hide whitespace
4 changes: 0 additions & 4 deletions stdlib/builtins.pyi
Show comments
View file
Open in desktop
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters. Learn more about bidirectional Unicode characters
Show hidden characters
Original file line number Diff line number Diff line change
Expand Up @@ -1153,10 +1153,6 @@ class list(MutableSequence[_T]):
@overload
def __setitem__(self, key: slice[SupportsIndex | None], value: Iterable[_T], /) -> None: ...
def __delitem__(self, key: SupportsIndex | slice[SupportsIndex | None], /) -> None: ...
# Overloading looks unnecessary, but is needed to work around complex mypy problems
@overload
def __add__(self, value: list[_T], /) -> list[_T]: ...
@overload
def __add__(self, value: list[_S], /) -> list[_S | _T]: ...

jorenham Jun 26, 2025

Copy link
Copy Markdown
Contributor

Choose a reason for hiding this comment

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

Choose a reason Spam Abuse Off Topic Outdated Duplicate Resolved Low Quality

maybe something like this could work?

Suggested change
def __add__(self, value: list[_S], /) -> list[_S | _T]: ...
def __add__(self: list[_S], value: list[_S], /) -> list[_S]: ...

randolf-scholz Jun 26, 2025 •
edited
Loading

Copy link
Copy Markdown
Contributor Author

Choose a reason for hiding this comment

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

Choose a reason Spam Abuse Off Topic Outdated Duplicate Resolved Low Quality

With this, wouldn't we get list[str] + list[int] = list[object] when checking with mypy, rather then list[str | int]?

I'd prefer python/mypy#19304 be fixed; then I think we would see most mypy-primer issues here go away. If you have seen this before and know and easier way to reproduce, please comment it.

jorenham Jun 26, 2025

Copy link
Copy Markdown
Contributor

Choose a reason for hiding this comment

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

Choose a reason Spam Abuse Off Topic Outdated Duplicate Resolved Low Quality

With this, wouldn't we get list[str] + list[int] = list[object] when checking with mypy, rather then list[str | int]?

With this, wouldn't we get list[str] + list[int] = list[object] when checking with mypy, rather then list[str | int]?

I'd prefer python/mypy#19304 be fixed; then I think we would see most mypy-primer issues here go away. If you have seen this before and know and easier way to reproduce, please comment it.

That's what I indeed expect here, given mypy's join vs union behavior. But if that's how they decide to behave, then that's up to them, afaik. At least it won't be rejected this way (is the hope)

randolf-scholz Jun 26, 2025

Copy link
Copy Markdown
Contributor Author

Choose a reason for hiding this comment

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

Choose a reason Spam Abuse Off Topic Outdated Duplicate Resolved Low Quality

Well, my goal with this PR was to reduce type-checker divergence, not to cement it.

jorenham Jun 26, 2025

Copy link
Copy Markdown
Contributor

Choose a reason for hiding this comment

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

Choose a reason Spam Abuse Off Topic Outdated Duplicate Resolved Low Quality

fair enough
def __iadd__(self, value: Iterable[_T], /) -> Self: ... # type: ignore[misc]
def __mul__(self, value: SupportsIndex, /) -> list[_T]: ...
Expand Down
Back | FazBrowse Home | New Git URL