@thi.ng/ramp/nested.js

Extensible keyframe interpolation/tweening of arbitrary, nested types

const nested = (children) => {
  const pairs = Object.entries(children);
  const $minmax = (op) => (acc, x) => pairs.reduce(
    (acc2, [id, impl]) => {
      acc2[id] = impl[op](acc2[id], x[id]);
      return acc2;
    },
    acc || {}
  );
  return {
    min: $minmax("min"),
    max: $minmax("max"),
    at: (stops, index, t) => pairs.reduce(
      (acc, [id, impl]) => {
        acc[id] = impl.at(
          stops.map((x) => [x[0], x[1][id]]),
          index,
          t
        );
        return acc;
      },
      {}
    )
  };
};
export {
  nested
};