export function memoize3<
A1 extends object,
A2 extends object,
A3 extends object,
R,
>(fn: (a1: A1, a2: A2, a3: A3) => R): (a1: A1, a2: A2, a3: A3) => R {
let cache0: WeakMap<A1, WeakMap<A2, WeakMap<A3, R>>>;
return function memoized(a1, a2, a3) {
if (cache0 === undefined) {
cache0 = new WeakMap();
}
let cache1 = cache0.get(a1);
if (cache1 === undefined) {
cache1 = new WeakMap();
cache0.set(a1, cache1);
}
let cache2 = cache1.get(a2);
if (cache2 === undefined) {
cache2 = new WeakMap();
cache1.set(a2, cache2);
}
let fnResult = cache2.get(a3);
if (fnResult === undefined) {
fnResult = fn(a1, a2, a3);
cache2.set(a3, fnResult);
}
return fnResult;
};
}