Disallow locally-generated types from escaping their function

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Assessment

Difficulty
5/5
Estimated time
Over a week
Newbie friendliness
20/100
Issue type
Feature
Clarity
Needs clarification
Activity status
Stale
Tech stack
python
Domain
compilers

Research direction

Start by tracing how NamedTuples declared inside functions and callable-generated subtype types are represented and whether they can escape their defining function. Investigate the coarse and fine-grained incremental interactions described in the issue. Done means locally generated types cannot escape the function without breaking supported type-checking and incremental behavior.

Written by the indexing model from the issue text.

Description

topic-runtime-semantics topic-variable-scope

We should ban locally generated types (such as NamedTuples declared inside of functions and types generated by uses of callable) from escaping the function where they are created.

It isn't really a good idea to do in the first place and it has difficult interactions with both coarse and finen-grained incremental.

Dominant language
Python
Stars
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Forks
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Avg merge
1d 18h
Merged PRs (30d)
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