no error when importing something that is conditionally defined
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Nobody has claimed this yet.
bug
topic-possibly-undefined
- Dominant language
- Python
- Stars
- 20.6k
- Forks
- 3.3k
- PR merge metrics
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Description
# foo.py
if bool():
a = 1
# bar.py
from foo import a # no error, crashes at runtime
i would expect an error like Name "a" may be undefined, which is what happens when you try to use it in the same file:
# foo.py
if bool():
a = 1
print(a) # error: Name "a" may be undefined
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Research direction
Reproduce the report with foo.py and bar.py, then trace mypy’s handling of from foo import a when a is only conditionally defined. Done means mypy reports that a may be undefined at the import site, consistently with the same-file example.
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Assessment
- Tech stack
- python
- Domain
- devtools
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 42/100