Skip to content

gh-145524: Update comment for TypeVar S in typing.rst #145525

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
hyperkai wants to merge 1 commit into
base: main
Choose a base branch
from
Open

gh-145524: Update comment for TypeVar S in typing.rst #145525

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
2 changes: 1 addition & 1 deletion Doc/library/typing.rst
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1809,7 +1809,7 @@ without the dedicated syntax, as documented below.
However, if desired, reusable type variables can also be constructed manually, like so::

T = TypeVar('T') # Can be anything
S = TypeVar('S', bound=str) # Can be any subtype of str
S = TypeVar('S', bound=str) # Can be str or any subtype of str
Copy link
Copy Markdown
Member

@encukou encukou Mar 10, 2026

Choose a reason for hiding this comment

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

With this wording, it looks like str is not a subtype of itself. Should we make it more clearly a clarification/note?

Suggested change
S = TypeVar('S', bound=str) # Can be str or any subtype of str
S = TypeVar('S', bound=str) # Can be any subtype of str (including exact str)

A = TypeVar('A', str, bytes) # Must be exactly str or bytes

Type variables exist primarily for the benefit of static type
Expand Down
Loading