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Is React.memo comparing deeply/recursive or at least deterministic JSON.stringify comparison? Or still going for shallow comparison?
by throwaway3265 8y ago
Is React.memo comparing deeply/recursive or at least deterministic JSON.stringify comparison? Or still going for shallow comparison?
- sophiebits 8y agoStill shallow. We usually recommend avoiding deep checks because (a) the concept of deep equality is pretty nebulous and hard to design in a predictable, precise way, and (b) deep equality checking can be slow, often just as slow (or slower) than the actual rerender – in which case the memoization is only hurting you. (If you want to do deep equality anyway, you can pass a second argument to React.memo to specify a custom comparator.)
- throwaway3265 8y agoI agree about those statements, just curious since that was probably the most important concept I had to learn about "advanced" React.
- deleted 8y ago[deleted]