From: "AlexandreMagro (Alexandre Magro) via ruby-core" <ruby-core@...>
Date: 2024-09-30T22:30:52+00:00
Subject: [ruby-core:119368] [Ruby master Feature#20770] A *new* pipe operator proposal

Issue #20770 has been updated by AlexandreMagro (Alexandre Magro).


ufuk (Ufuk Kayserilioglu) wrote in #note-8: 
> You can also make the whole pipeline with just using procs:
> ```ruby
> (-> { URI.parse(it) } >> -> { Net::HTTP.get(it) } >> -> { JSON.parse(it) } >> -> { it.fetch("title") }).call(client_api_url)
> #=> "sunt aut facere repellat provident occaecati excepturi optio reprehenderit"
> ```

Yes, and it's also possible to achieve this with a chain of `.then`, which results in a similar structure. The idea of the pipe operator is to be syntactic sugar, bringing functionality from functional languages into Ruby without introducing any complexity, while maintaining ruby's simplicity.

```ruby
client_api_url
  .then { URI.parse(it) }
  .then { Net::HTTP.get(it) }
  .then { JSON.parse(it).fetch(important_key) }
```

----------------------------------------
Feature #20770: A *new* pipe operator proposal
https://bugs.ruby-lang.org/issues/20770#change-109981

* Author: AlexandreMagro (Alexandre Magro)
* Status: Open
----------------------------------------
Hello,

This is my first contribution here. I have seen previous discussions around introducing a pipe operator, but it seems the community didn't reach a consensus. I would like to revisit this idea with a simpler approach, more of a syntactic sugar that aligns with how other languages implement the pipe operator, but without making significant changes to Ruby's syntax.

Currently, we often write code like this:

```ruby
value = half(square(add(value, 3)))
```

We can achieve the same result using the `then` method:

```ruby
value = value.then { add(_1, 3) }.then { square(_1) }.then { half(_1) }
```

While `then` helps with readability, we can simplify it further using the proposed pipe operator:

```ruby
value = add(value, 3) |> square(_1) |> half(_1)
```

Moreover, with the upcoming `it` feature in Ruby 3.4 (#18980), the code could look even cleaner:

```ruby
value = add(value, 3) |> square(it) |> half(it)
```

This proposal uses the anonymous block argument `(_1)`, and with `it`, it simplifies the code without introducing complex syntax changes. It would allow us to achieve the same results as in other languages that support pipe operators, but in a way that feels natural to Ruby, using existing constructs like `then` underneath.

I believe this operator would enhance code readability and maintainability, especially in cases where multiple operations are chained together.

Thank you for considering this proposal!






-- 
https://bugs.ruby-lang.org/
 ______________________________________________
 ruby-core mailing list -- ruby-core@ml.ruby-lang.org
 To unsubscribe send an email to ruby-core-leave@ml.ruby-lang.org
 ruby-core info -- https://ml.ruby-lang.org/mailman3/lists/ruby-core.ml.ruby-lang.org/