#209

src/tools/useGuaranteedMemo.ts

@@ -1,15 +1,17 @@
-import { useRef } from "react";
+import { useState } from "react";
 
 /** Like react's useMemo but with guarantee that the fn
  * won't be invoked again if deps hasn't change */
 export function useGuaranteedMemo<T>(
     fn: () => T,
     deps: React.DependencyList
 ): T {
-    const ref = useRef<{ v: T; prevDeps: unknown[] }>();
+    const [ref] = useState<{
+        current: { v: T; prevDeps: unknown[] } | undefined;
+    }>({ "current": undefined });
 
     if (
-        !ref.current ||
+        ref.current === undefined ||
         deps.length !== ref.current.prevDeps.length ||
         ref.current.prevDeps.map((v, i) => v === deps[i]).indexOf(false) >= 0
     ) {