microsoft / microsoft/TypeScript

Explicit any type in for..in loop

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Description

For the reason of consistency, it should be possible to explicitly annotate the iterator variable at least with the "any" type in a for..in loop.

Edit from @sandersn: Fixes should apply to JSDoc too: https://github.com/microsoft/TypeScript/issues/43756, and perhaps allow annotations on for .. of too

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Research direction

The issue names no source files or tests. Start by locating the parser and checker paths for for..in iterator declarations, then review the related JSDoc issue #43756 and existing tests for loop-variable annotations. Done means explicit any is accepted consistently in the requested for..in syntax, with the JSDoc case addressed as specified.

Written by the indexing model from the issue text.

Assessment

Tech stack
javascript, typescript
Domain
compilers
Issue type
Feature
Difficulty
4/5
Estimated time
3-5 days
Activity status
Active
Clarity
Mostly clear
Newbie friendliness
48/100

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