17 lines
589 B
TypeScript
17 lines
589 B
TypeScript
import { useRef } from '../lib/teact/teact';
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function usePrevious<T extends any>(next: T): T | undefined;
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function usePrevious<T extends any>(next: T, shouldSkipUndefined: true): Exclude<T, undefined> | undefined;
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function usePrevious<T extends any>(next: T, shouldSkipUndefined?: boolean): Exclude<T, undefined> | undefined;
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function usePrevious<T extends any>(next: T, shouldSkipUndefined?: boolean) {
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const ref = useRef<T>();
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const { current } = ref;
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if (!shouldSkipUndefined || next !== undefined) {
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ref.current = next;
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}
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return current;
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}
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export default usePrevious;
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