[3.8] bpo-36541: lib2to3: Support named assignment expressions (GH-12702) #19315
Conversation
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
There are two copies of the grammar -- the one used by Python itself as Grammar/Grammar, and the one used by lib2to3 which has necessarily diverged at Lib/lib2to3/Grammar.txt because it needs to support older syntax an we want it to be reasonable stable to avoid requiring fixer rewrites. This brings suport for syntax like `if x:= foo():` to match what the live Python grammar does. This should've been added at the time of the walrus operator itself, but lib2to3 being independent is often overlooked. So we do consider this a bugfix rather than enhancement. (cherry picked from commit 3c3aa45) Co-authored-by: Tim Hatch <[email protected]>
bedevere-bot
added
type-bug
gpshead
changed the title
gpshead
approved these changes
Apr 2, 2020
1 similar comment
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
There are two copies of the grammar -- the one used by Python itself as
Grammar/Grammar, and the one used by lib2to3 which has necessarily diverged at
Lib/lib2to3/Grammar.txt because it needs to support older syntax an we want it
to be reasonable stable to avoid requiring fixer rewrites.
This brings suport for syntax like
if x:= foo():to match what the livePython grammar does.
This should've been added at the time of the walrus operator itself, but lib2to3 being
independent is often overlooked. So we do consider this a bugfix rather than enhancement.
(cherry picked from commit 3c3aa45)
Co-authored-by: Tim Hatch [email protected]
https://bugs.python.org/issue36541
Automerge-Triggered-By: @gpshead