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

zverok (Victor Shepelev) wrote in #note-4:
> I'd say that `(5..14) / 3` reads definitely like "split the range into 3 parts" (expecting, IDK, 3 sub-ranges or jumps over `(14-5) / 3` spans).

x / y reads "divide x by y", not "divide x into y parts". Following this, `(5..14) / 3` divides `5..14` by `3`, yielding the quotient sets `[5, 6, 7]`, `[8, 9, 10]`, `[11, 12, 13]`, and `[14]`. Iterating over the those quotient sets, taking the representative element from each set gives, `5, 8, 11, 14`.

If you don't know what a quotient set is, please take a look at the link I have provided.

----------------------------------------
Feature #16818: Rename `Range#%` to `Range#/`
https://bugs.ruby-lang.org/issues/16818#change-85298

* 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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