@mui/material/utils/mergeSlotProps.d.ts

Material UI is an open-source React component library that implements Google's Material Design. It's comprehensive and can be used in production out of the box.

import { SlotComponentProps } from '@mui/utils';
export default function mergeSlotProps<T extends SlotComponentProps<React.ElementType, {}, {}>, K = T, U = (T extends Function ? T : K extends Function ? K : T extends undefined ? K : T)>(externalSlotProps: T | undefined, defaultSlotProps: K): U;