python / python/mypy

mypy gives 'not defined' error for use after global declaration

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#5,732 2 comments 4 reactions 0 assignees View on GitHub

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bug false-positive priority-1-normal topic-runtime-semantics topic-variable-scope
Dominant language
Python
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Description

In version 0.630 and master (with Python 3.7.0), I get this error :

def foo() -> None:
    global myglobal
    myglobal = 2  # error: Name 'myglobal' is not defined

I thought that I should not get an error. Is this behavior correct?

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Research direction

The report provides a minimal Python reproducer but names no source file or test location. Run the example first, then trace mypy's handling of global declarations and add or update coverage for this case; done means the diagnostic matches the intended Python behavior.

Written by the indexing model from the issue text.

Assessment

Tech stack
python
Domain
devtools
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

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