code: function pipeP() {
  	  if (arguments.length === 0) {
  	    throw new Error('pipeP requires at least one argument');
  	  }
  	  return _arity(arguments[0].length, reduce(_pipeP, arguments[0], tail(arguments)));
  	}
docs: Performs left-to-right composition of one or more Promise-returning
  functions. The leftmost function may have any arity; the remaining functions
  must be unary.
  
  @func
  @memberOf R
  @since v0.10.0
  @category Function
  @sig ((a -> Promise b), (b -> Promise c), ..., (y -> Promise z)) -> (a -> Promise z)
  @param {...Function} functions
  @return {Function}
  @see R.composeP
  @example
  
  //  followersForUser :: String -> Promise [User]
  var followersForUser = R.pipeP(db.getUserById, db.getFollowers);