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compose.js

/**
 * Composes single-argument functions from right to left. The rightmost
 * function can take multiple arguments as it provides the signature for
 * the resulting composite function.
 *
 * @param {...Function} funcs The functions to compose.
 * @returns {Function} A function obtained by composing the argument functions
 * from right to left. For example, compose(f, g, h) is identical to doing
 * (...args) => f(g(h(...args))).
 */

export default function compose(...funcs) {
  if (funcs.length === 0) {
    return arg => arg;
  }

  const last = funcs[funcs.length - 1];
  const rest = funcs.slice(0, -1);
  return (...args) => rest.reduceRight((composed, f) => f(composed), last(...args));
}

Solution can be found here facebook/flow#1950 (comment)