Memoize a function with argument equality

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Memoize a function with argument equality · UIHero

Memoize a function with argument equality

Cache function results using an injected positional equality strategy while preserving receiver semantics.

MediumJavaScript Performance

50 min0% acceptance

Description

Implement memoize for arbitrary functions. Calls whose argument lists compare equal reuse the cached result, unequal calls compute once, undefined is cacheable, this is preserved, and neither arguments nor returned records are mutated by the wrapper.

Requirements

The solution exports the required memoize API from the editable module.
Cache hit works deterministically for the documented normal, boundary, and repeated-use scenarios.
Cache miss works deterministically for the documented normal, boundary, and repeated-use scenarios.
Argument equality works deterministically for the documented normal, boundary, and repeated-use scenarios.
Preserves this works deterministically for the documented normal, boundary, and repeated-use scenarios.
Caches undefined works deterministically for the documented normal, boundary, and repeated-use scenarios.
Caller-owned inputs and nested values remain unchanged after the operation completes.

Custom object equality

Input

Call twice with distinct { id: 7 } objects and equality comparing id

Expected output

The wrapped function executes once and the second call reuses its result

Explanation

Equality is applied position by position across the complete argument tuple.

Constraints

Preserve the original receiver on cache misses
Cache undefined results
Do not mutate or freeze argument values

Hints

Hint 1

Store argument tuples separately from cached results.

Hint 2

A hit requires equal lengths and equality at every position.

Hint 3

Use an explicit found flag so undefined can represent a valid cached value.

memoizationfunctionsequality

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