reactjs / reactjs/react.dev

useMemo - must the create function be a pure function?

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JavaScript
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Description

The doc is not clear if the useMemo "create" function must be a pure function. A pure function must depend on its inputs to generate output.

Can the "create" function read the content of a ref? This would make it impure, but can such a function be used in the useMemo hook?

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First steps

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  3. Fork the repository and make your change on a branch.
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Research direction

Start by locating the useMemo documentation and reviewing how it describes the create function and dependencies. Clarify whether reading ref contents is supported, and consider the work complete when the documentation directly answers the purity question and explains the relevant constraint.

Written by the indexing model from the issue text.

Assessment

Tech stack
react
Domain
documentation
Issue type
Documentation
Difficulty
2/5
Estimated time
1-3 hours
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
35/100

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