[ruby-core:81396] [Ruby trunk Feature#13600] yield_self should be chainable/composable

Issue #13600 has been updated by avit (Andrew Vit).


In case the description is unclear, the goal is to support something like this:

```
pipeline = (&:upcase).yield_self(&:reverse)
"ruby".yield_self(pipeline)
#=> "YRUB"
```

or else:

```
pipeline = (&:upcase) | (&:reverse)
"ruby".yield_self(pipeline)
#=> "YRUB"
```


----------------------------------------
Feature #13600: yield_self should be chainable/composable
https://bugs.ruby-lang.org/issues/13600#change-65108

* Author: avit (Andrew Vit)
* Status: Open
* Priority: Normal
* Assignee: 
* Target version: 
----------------------------------------
One of the main use cases that would make `yield_self` a helpful addition is to build functional pipelines (function composition). This is currently not possible since Proc/Lambda do not handle `yield_self` in the expected way.

I believe that `callable.yield_self(&other)` should build up a composition, something like this:


```
class Proc
  def yield_self(&other)
    proc { |input| other.call( self.call(input) ) }
  end
end
```

I originally proposed an example for this using pipe `|` syntax here:

https://bugs.ruby-lang.org/issues/10095#note-22

Maybe Proc should use `|` or `&` for this syntax instead of changing `yield_self` directly.



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