[ruby-core:85443] [CommonRuby Feature#13581] Syntax sugar for method reference

[artur.roszczyk@gmail.com]

Issue #13581 has been updated by sevos (Artur Roszczyk).


phluid61 (Matthew Kerwin) wrote:
> sevos (Artur Roszczyk) wrote:
> > 
> > What are your thoughts?
> 
> I have two:
> 
> 1. As always: do we really need more magic symbols?  I like reading Ruby because it's *not* Perl.
I totally agree, but we still like -> {} syntax for lambdas, right? Let's play with ideas, maybe we can find something nice for a method selector, too ;)

> 
> 2. If you're adding new syntax, you don't have to be clever. Symbol has `:"#{x}"` so why not propose `y:::"#{x}"`? Not that it adds much over `y.method(x)`

You're totally right! I was looking at triple-colon as an operator taking two arguments. Your idea of looking at this as a double-colon lookup operator is actually great, look:

~~~ruby
irb(main):006:0> a :: :to_s
SyntaxError: (irb):6: syntax error, unexpected tSYMBEG, expecting '('
a :: :to_s
      ^
	from /Users/sevos/.rbenv/versions/2.4.0/bin/irb:11:in `<main>'
irb(main):007:0> Kernel :: :t
SyntaxError: (irb):7: syntax error, unexpected tSYMBEG, expecting tCONSTANT
A :: :t
      ^
	from /Users/sevos/.rbenv/versions/2.4.0/bin/irb:11:in `<main>'
~~~

We already have a lookup operator which takes object, constant on the left side and method name or constand on the right side.
Maybe it would be possible to support symbols on the right side and expand them to `method(:symbol)` call?
I would like just to emphasise again the need of respecting the method-to-be-called visibility depending on the current binding.


----------------------------------------
Feature #13581: Syntax sugar for method reference
https://bugs.ruby-lang.org/issues/13581#change-70226

* Author: americodls (Americo Duarte)
* Status: Open
* Priority: Normal
* Assignee: 
* Target version: 
----------------------------------------
Some another programming languages (even Java, in version 8) has a cool way to refer a method as a reference.

I wrote some examples here: https://gist.github.com/americodls/20981b2864d166eee8d231904303f24b

I miss this thing in ruby.

I would thinking if is possible some like this:

~~~
roots = [1, 4, 9].map &Math.method(:sqrt)
~~~

Could be like this:

~~~
roots = [1, 4, 9].map Math->method
~~~

What do you guys thinking about it?



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