[#97652] [Ruby master Feature#16746] Endless method definition — mame@...

Issue #16746 has been reported by mame (Yusuke Endoh).

24 messages 2020/04/01

[#97655] [Ruby master Misc#16747] Repository reorganization request — shyouhei@...

Issue #16747 has been reported by shyouhei (Shyouhei Urabe).

12 messages 2020/04/01

[#97745] [Ruby master Bug#16769] Struct.new(..., immutable: true) — takashikkbn@...

Issue #16769 has been reported by k0kubun (Takashi Kokubun).

10 messages 2020/04/08

[#97803] [Ruby master Misc#16775] DevelopersMeeting20200514Japan — mame@...

Issue #16775 has been reported by mame (Yusuke Endoh).

20 messages 2020/04/10

[#97810] [Ruby master Bug#16776] Regression in coverage library — deivid.rodriguez@...

Issue #16776 has been reported by deivid (David Rodr刕uez).

11 messages 2020/04/10

[#97828] [Ruby master Misc#16778] Should we stop vendoring default gems code? — deivid.rodriguez@...

Issue #16778 has been reported by deivid (David Rodr刕uez).

37 messages 2020/04/11

[#97878] [Ruby master Feature#16786] Light-weight scheduler for improved concurrency. — samuel@...

Issue #16786 has been reported by ioquatix (Samuel Williams).

72 messages 2020/04/14

[#97893] [Ruby master Bug#16787] [patch] allow Dir.home to work for non-login procs when $HOME not set — salewski@...

Issue #16787 has been reported by salewski (Alan Salewski).

18 messages 2020/04/15

[#97905] [Ruby master Feature#16791] Shortcuts for attributes of Process::Status — 0xfffffff0@...

Issue #16791 has been reported by 0x81000000 (/ /).

10 messages 2020/04/16

[#97907] [Ruby master Bug#16792] Make Mutex held per Fiber instead of per Thread — eregontp@...

Issue #16792 has been reported by Eregon (Benoit Daloze).

9 messages 2020/04/16

[#97989] [Ruby master Misc#16802] Prefer use of RHS assigment in documentation — samuel@...

Issue #16802 has been reported by ioquatix (Samuel Williams).

10 messages 2020/04/21

[#97992] [Ruby master Misc#16803] Discussion: those internal macros reside in public API headers — shyouhei@...

Issue #16803 has been reported by shyouhei (Shyouhei Urabe).

14 messages 2020/04/21

[#98026] [Ruby master Bug#16809] ruby testsuite fails on s390x alpine (musl) with --with-coroutine=copy — ncopa@...

Issue #16809 has been reported by ncopa (Natanael Copa).

11 messages 2020/04/23

[#98034] [Ruby master Feature#16812] Allow slicing arrays with ArithmeticSequence — zverok.offline@...

Issue #16812 has been reported by zverok (Victor Shepelev).

12 messages 2020/04/23

[#98044] [Ruby master Bug#16814] Segmentation fault in GC while running test/ruby/test_fiber.rb on s390x — Rei.Odaira@...

Issue #16814 has been reported by ReiOdaira (Rei Odaira).

14 messages 2020/04/24

[#98059] [Ruby master Bug#16816] Prematurely terminated Enumerator should stay terminated — headius@...

Issue #16816 has been reported by headius (Charles Nutter).

9 messages 2020/04/24

[#98066] [Ruby master Feature#16818] Rename `Range#%` to `Range#/` — sawadatsuyoshi@...

Issue #16818 has been reported by sawa (Tsuyoshi Sawada).

11 messages 2020/04/26

[ruby-core:98068] [Ruby master Feature#16818] Rename `Range#%` to `Range#/`

From: shevegen@...
Date: 2020-04-26 16:55:00 UTC
List: ruby-core #98068
Issue #16818 has been updated by shevegen (Robert A. Heiler).


I somewhat agree with sawa's comment that % on Range may confuse some ruby
folks; I think % is more typically the modulo operator? I can not say how
strong this confusion may be, perhaps small, perhaps not, but I concur with
his original comment in regards to %.

However had, I also happily admit that I really have no particularly strong
opinion either way. I am also indifferent (or, more accurately, a bit 
clueless) about /. Since it is quite unlikely for me to use % or / on 
Range anyway (I tend to stick to oldschool matz-ruby whenever possible ;)),
I let those folks who make use of the range operation, or those who 
proposed it, to comment on that either way since I am not really attached
to that operation to begin with.

It should be pointed out that this has follow-up effects - see zverok's 
example of extending it towards Arithmetic* (and there I also don't have
a big opinion either way, just wanted to point out it that whatever way
is chosen, it may be good to decide on it before ruby 3.0 release I
think).

----------------------------------------
Feature #16818: Rename `Range#%` to `Range#/`
https://bugs.ruby-lang.org/issues/16818#change-85295

* Author: sawa (Tsuyoshi Sawada)
* Status: Open
* Priority: Normal
----------------------------------------
`Range#%` was introduced as an alias of `Range#step` by 14697, but it is counter-intuitive and confusing.

Iteration in the following:

```ruby
((5..14) % 3).each{|i| p i}
#>> 5
#>> 8
#>> 11
#>> 14
```

is not based on `x % y` in any sense. In fact, actually applying `% 3` to the selected elements returns a unique value `2`, and it is not obvious how this is related to the iteration.

```ruby
[5, 8, 11, 14].map{|i| i % 3}
# => [2, 2, 2, 2]
```

Rather, the concept seems to be based on `/`. Applying `/ 3` to the relevant elements returns a sequence `1, 2, 3, 4`.

```ruby
[5, 8, 11, 14].map{|i| i / 3}
# => [1, 2, 3, 4]
```

Hence, `(5..14).step(3)` can be interpreted like this: Iterate over the [equivalence class](https://en.wikipedia.org/wiki/Equivalence_class) (quotient set) of range `5..14` yielded by `/ 3`.

Notice that the number of elements in `[5, 8, 11, 14]` is 4, which is `(14 - 5 + 1) / 3.0).ceil`, but is not related to `%`.

So I propose that the alias of `Range#step` should be `Range#/`, and `Range#%` should be deprecated as soon as possible before its use accumulates:

```ruby
((5..14) / 3).each{|i| p i}
#>> 5
#>> 8
#>> 11
#>> 14
```

---

P.S.

And if `Range#%` were to be introduced at all, I would rather expect it to behave like the following:

```ruby
((5..14) % 3).each{|i| p i}
#>> 5
#>> 6
#>> 7
```

which is why I claimed above that the current `Range#%` is confusing.



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