[ruby-core:118751] [Ruby master Feature#20657] Allow Enumerable#map(&:method) and #each accept additional parameters for method

Issue #20657 has been updated by nobu (Nobuyoshi Nakada).

Status changed from Open to Feedback

ukolovda (Dmitry Ukolov) wrote in #note-3:
> Oo, the ampersand is not language syntax, as I think before, but simple operator, converting Symbol to Proc. It is fine trix, but cannot accept additional arguments.

You mean ampersand+colon(`&:`)?

"Additional parameters" feature has been requested many times and in many ways (including the same as your proposal) already, but no acceptable solution.
Instead, numbered parameters (`_1`, `_2`, ...) and `it` parameter have been introduced.

----------------------------------------
Feature #20657: Allow Enumerable#map(&:method) and #each accept additional parameters for method
https://bugs.ruby-lang.org/issues/20657#change-109295

* Author: ukolovda (Dmitry Ukolov)
* Status: Feedback
----------------------------------------
I can use `#map` (or `#each`) with short method name, for example:

``` ruby
a = ["a1", "b1", "c1"]

b = a.map(&:length)
# or
a.each(&:some_method)
```

But with additional arguments I must use yield:

```ruby
c = a.map { |item| item.ljust(10) }
# or
a.each { |item| item.some_method(arg1, arg2) }
```

Direct sending allow make the code more simple:
```ruby
c = a.map(&:ljust, 10) # Now give syntax error, unexpected ',', expecting ')'
# or
a.each(&:some_method, arg1, arg2) # Now give syntax error, unexpected ',', expecting ')'
```




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