20 lines
631 B
JavaScript
20 lines
631 B
JavaScript
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import * as React from 'react';
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/**
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* @internal
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* Checks if components was mounted the first time.
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* Since concurrent mode will be released in the future this needs to be verified
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* Currently (React 17) will always render the initial mount once
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* https://codesandbox.io/s/heuristic-brook-s4w0q?file=/src/App.jsx
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* https://codesandbox.io/s/holy-grass-8nieu?file=/src/App.jsx
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*
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* @example
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* const isFirstMount = useFirstMount();
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*/ export function useFirstMount() {
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const isFirst = React.useRef(true);
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if (isFirst.current) {
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isFirst.current = false;
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return true;
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}
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return isFirst.current;
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}
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