55 строки
1.3 KiB
JavaScript
55 строки
1.3 KiB
JavaScript
/**
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* Copyright (c) Facebook, Inc. and its affiliates.
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*
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* This source code is licensed under the MIT license found in the
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* LICENSE file in the root directory of this source tree.
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*
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* @format
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* @flow strict-local
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*/
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'use strict';
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const React = require('react');
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/**
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* Renders static content efficiently by allowing React to short-circuit the
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* reconciliation process. This component should be used when you know that a
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* subtree of components will never need to be updated.
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*
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* const someValue = ...; // We know for certain this value will never change.
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* return (
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* <StaticContainer>
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* <MyComponent value={someValue} />
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* </StaticContainer>
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* );
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*
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* Typically, you will not need to use this component and should opt for normal
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* React reconciliation.
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*/
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type Props = $ReadOnly<{|
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/**
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* Whether or not this component should update.
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*/
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shouldUpdate: ?boolean,
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/**
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* Content short-circuited by React reconciliation process.
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*/
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children: React.Node,
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|}>;
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class StaticContainer extends React.Component<Props> {
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shouldComponentUpdate(nextProps: Props): boolean {
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return !!nextProps.shouldUpdate;
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}
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render() {
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const child = this.props.children;
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return child === null || child === false
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? null
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: React.Children.only(child);
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}
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}
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module.exports = StaticContainer;
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