17 lines
418 B
JavaScript
17 lines
418 B
JavaScript
// @flow
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let weakMemoize = function <Arg, Return>(func: Arg => Return): Arg => Return {
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// $FlowFixMe flow doesn't include all non-primitive types as allowed for weakmaps
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let cache: WeakMap<Arg, Return> = new WeakMap()
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return arg => {
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if (cache.has(arg)) {
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// $FlowFixMe
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return cache.get(arg)
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}
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let ret = func(arg)
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cache.set(arg, ret)
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return ret
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}
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}
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export default weakMemoize
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