src/vs/base/common/cache.ts/LRUCachedComputed/get
class LRUCachedComputed:	public get(arg: TArg): TComputed {
		const key = JSON.stringify(arg);
		if (this.lastArgKey !== key) {
			this.lastArgKey = key;
			this.lastCache = this.computeFn(arg);
		}
		return this.lastCache!;
	}