[ruby-core:93130] [Ruby trunk Feature#15799] pipeline operator

[keystonelemur@gmail.com]

Issue #15799 has been updated by baweaver (Brandon Weaver).


That's a very fair point @jeremyevans0, it would introduce two lookup chains even under the most ideal of circumstances. Perhaps if `&` were slightly extended, one could do this:

```ruby
def double(n) n * 2 end

increment = -> n { n + 1 }

5
|> &double
|> &increment
|> to_s(2)
|> reverse
|> to_i
```

...wherein `&` would retain its meaning of coercing something to a proc, make the call chain more explicit, and kill the speed hit potential.

The downside is it would add a feature to `&` that it could convert a method to a proc which does not currently exist and would do all types of interesting things to the interpreter for parens. It had been mentioned in the past to have anonymous or self-oriented `.:` to get around this:

```ruby
5
|> &.:double
|> &increment
|> to_s(2)
|> reverse
|> to_i
```

Though that presents issues of 2+ arity functions. It's certainly a hard issue to solve for, but if a solution can be found it would be extremely powerful for the language.

----------------------------------------
Feature #15799: pipeline operator
https://bugs.ruby-lang.org/issues/15799#change-78559

* Author: nobu (Nobuyoshi Nakada)
* Status: Closed
* Priority: Normal
* Assignee: 
* Target version: 
----------------------------------------
Implemented the pipeline operator `|>`, a topic of "ruby committers vs the world" in RubyKaigi 2019.
Also a casual idea of rightward assignment.

```ruby
1.. |> take 10 |> map {|e| e*2} |> (x)
p x #=> [2, 4, 6, 8, 10, 12, 14, 16, 18, 20]
```

https://github.com/nobu/ruby/tree/feature/pipeline




-- 
https://bugs.ruby-lang.org/