[v5]: refactor useMemoSelector

pmndrs · Jan 20, 2024 · b3c8b15 · b3c8b15
1 parent 43986a3
commit b3c8b15
Show file tree

Hide file tree

Showing 2 changed files with 5 additions and 7 deletions.
diff --git a/src/react.ts b/src/react.ts
@@ -25,15 +25,13 @@ const useMemoSelector = <TState, StateSlice>(
   selector: (state: TState) => StateSlice,
 ) =>
   useMemo(() => {
-    let lastSlice: StateSlice
-    let lastState: TState
+    let prev: readonly [TState, StateSlice] | undefined
     return () => {
       const state = getState()
-      if (!Object.is(lastState, state)) {
-        lastSlice = selector(state)
-        lastState = state
+      if (!prev || !Object.is(prev[0], state)) {
+        prev = [state, selector(state)]
       }
-      return lastSlice
+      return prev[1]
     }
   }, [getState, selector])
 

diff --git a/src/react/shallow.ts b/src/react/shallow.ts
@@ -1,4 +1,4 @@
-// import { useDebugValue } from 'react'
+// import { useRef } from 'react'
 // That doesnt work in ESM, because React libs are CJS only.
 // The following is a workaround until ESM is supported.
 // eslint-disable-next-line import/extensions