From: muraken@... Date: 2018-04-23T13:56:52+00:00 Subject: [ruby-core:86656] [CommonRuby Feature#14697] Introducing Range#% as an alias to Range#step Issue #14697 has been updated by mrkn (Kenta Murata). I'm supposing that this new notation of Range#step is mostly used for slicing numerical arrays like Numo::NArray. This usecase is very similar to Python's slice notation used for slicing numpy's arrays. With this new notation, `ary[::2]` in python can be written as `ary[(0...)%2]` in Ruby 2.6. Slicing an array with a stepped range is often used in data analysis. For example, if daru supports this new notation, we can pick up even rows in a dataframe `df` by `df.row[(0..)%2]`. ---------------------------------------- Feature #14697: Introducing Range#% as an alias to Range#step https://bugs.ruby-lang.org/issues/14697#change-71613 * Author: mrkn (Kenta Murata) * Status: Open * Priority: Normal * Assignee: matz (Yukihiro Matsumoto) * Target version: ---------------------------------------- In #13904, `Enumerator::ArithmeticSequence` has been accepted for the representation of a range with step value. And in #12912, a new syntax of endless range `(1..)` has been accepted. Combining these new features, we can write an endless step range like `(1..).step(2)` in Ruby 2.6. It can be used for array slicing like python's `1::2`. If `Range#%` is introduced as an alias to `Range#step`, we can write a step range like `(1..)%2`. This notation is already introduced numo-narray. -- https://bugs.ruby-lang.org/ Unsubscribe: