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Function: memoize()

memoize<Args, R>(fn, options?): MemoizedFunction<Args, R>

Defined in: memo/memoize/index.ts:32

Creates a memoized version of a function that caches results based on arguments.

By default, uses a simple Map cache with the first argument as the key. For multi-argument functions or complex keys, use memoizeBy() instead.

Type Parameters​

Args​

Args extends readonly [unknown, unknown]

R​

R

Parameters​

fn​

(...args) => R

options?​

MemoizeOptions = {}

Returns​

MemoizedFunction<Args, R>

Example​

// Basic memoization
const fibonacci = (n: number): number => {
  if (n <= 1) return n
  return fibonacci(n - 1) + fibonacci(n - 2)
}

const memoFib = memoize(fibonacci)
memoFib(40) // computed (takes time)
memoFib(40) // cached (instant)

// With max size
const getUser = memoize(fetchUser, { maxSize: 100 })

// With TTL
const getWeather = memoize(fetchWeather, { ttl: 5 * 60 * 1000 }) // 5 min

See​

  • memoizeBy - for custom key extraction
  • memoizeAsync - for async functions with deduplication