26 lines
779 B
JavaScript
26 lines
779 B
JavaScript
/**
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* External dependencies
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*/
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import { useRef } from '@wordpress/element';
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import isShallowEqual from '@wordpress/is-shallow-equal';
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/**
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* A custom hook that compares the provided value across renders and returns the
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* previous instance if shallow equality with previous instance exists.
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*
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* This is particularly useful when non-primitive types are used as
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* dependencies for react hooks.
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*
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* @param {mixed} value Value to keep the same if satisfies shallow equality.
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*
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* @return {mixed} The previous cached instance of the value if the current has
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* shallow equality with it.
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*/
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export const useShallowEqual = ( value ) => {
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const ref = useRef();
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if ( ! isShallowEqual( value, ref.current ) ) {
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ref.current = value;
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}
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return ref.current;
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};
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