Prototype User Guide-range. js

A Range object is a "Range" Object inherited from Enumerable. You can regard it as [x, x + 1, x + 2, x + 3 ...... array x + n], but it saves storage space than such array, because the range object only saves x and x + n. To create a Range object, you can call the $ R (start, end, exclusive) method to specify whether to include the end, if the value is not specified or false, end is included. Otherwise, you can use the method defined in Enumerable to operate the range object, the range object only implements the enumeration logic _ each required by the Enumerable object and overwrites the include method.