36 lines
740 B
Markdown
36 lines
740 B
Markdown
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# @emotion/weak-memoize
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> A memoization function that uses a WeakMap
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## Install
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```bash
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yarn add @emotion/weak-memoize
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```
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## Usage
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Because @emotion/weak-memoize uses a WeakMap the argument must be a non primitive type, e.g. objects, functions, arrays and etc. The function passed to `weakMemoize` must also only accept a single argument.
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```jsx
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import weakMemoize from '@emotion/weak-memoize'
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let doThing = weakMemoize(({ someProperty }) => {
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return { newName: someProperty }
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})
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let obj = { someProperty: true }
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let firstResult = doThing(obj)
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let secondResult = doThing(obj)
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firstResult === secondResult // true
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let newObj = { someProperty: true }
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let thirdResult = doThing(newObj)
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thirdResult === firstResult // false
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```
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