30 lines
781 B
Plaintext
30 lines
781 B
Plaintext
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/**
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* Copyright (c) 2013-present, Facebook, Inc.
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* All rights reserved.
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*
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* This source code is licensed under the BSD-style license found in the
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* LICENSE file in the root directory of this source tree. An additional grant
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* of patent rights can be found in the PATENTS file in the same directory.
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*
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* @providesModule memoizeStringOnly
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* @flow
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* @typechecks static-only
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*/
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'use strict';
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/**
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* Memoizes the return value of a function that accepts one string argument.
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*/
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function memoizeStringOnly<T>(callback: (s: string) => T): (s: string) => T {
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const cache = {};
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return function (string) {
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if (!cache.hasOwnProperty(string)) {
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cache[string] = callback.call(this, string);
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}
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return cache[string];
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};
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}
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module.exports = memoizeStringOnly;
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