Function createLoopUpdate

packages/core/src/SpringValue.ts:1062–1096

(
  props: T & { loop?: any; to?: any; from?: any; reverse?: any },
  loop = props.loop,
  to = props.to
)

}

export function createLoopUpdate<T>(
  props: T & { loop?: any; to?: any; from?: any; reverse?: any },
  loop = props.loop,
  to = props.to
): T | undefined {
  const loopRet = callProp(loop)
  if (loopRet) {
    const overrides = loopRet !== true && inferTo(loopRet)
    const reverse = (overrides || props).reverse
    const reset = !overrides || overrides.reset
    return createUpdate({
      ...props,
      loop,

      // Avoid updating default props when looping.
      default: false,

      // Never loop the `pause` prop.
      pause: undefined,

      // For the "reverse" prop to loop as expected, the "to" prop
      // must be undefined. The "reverse" prop is ignored when the
      // "to" prop is an array or function.
      to: !reverse || isAsyncTo(to) ? to : undefined,

      // Ignore the "from" prop except on reset.
      from: reset ? props.from : undefined,
      reset,

      // The "loop" prop can return a "useSpring" props object to
      // override any of the original props.
      ...overrides,
    })
  }
}

/**
 * Return a new object based on the given `props`.