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export function memo<TDeps extends readonly any[], TResult>(
  getDeps: () => [...TDeps],
  fn: (...args: NoInfer<[...TDeps]>) => TResult,
  opts: {
    key: any
    debug?: () => any
    onChange?: (result: TResult) => void
  }
): () => TResult {
  let deps: any[] = []
  let result: TResult | undefined

  return () => {
    let depTime: number
    if (opts.key && opts.debug) depTime = Date.now()

    const newDeps = getDeps()

    const depsChanged =
      newDeps.length !== deps.length ||
      newDeps.some((dep: any, index: number) => deps[index] !== dep)

    if (!depsChanged) {
      return result!
    }

    deps = newDeps

    let resultTime: number
    if (opts.key && opts.debug) resultTime = Date.now()

    result = fn(...newDeps)
    opts?.onChange?.(result)

    return result!
  }
}