Feature #21693: Allow calling any callable object as a method

• Status: Open
• Assignee: -
• Target version: -

[cheba (Alexander Mankuta)]

Callable objects are popular in Ruby. A very common pattern of Service objects with a single public call method can be found in many Rails apps, too.

I propose to extend syntax so that adding () to any object that has a call method to work as a method invocation.

Example:

class Greeter
  def call(name)
    puts "Hello, #{name}!"
  end
end

hello = Greeter.new

hello("World") # => Hello, World!

We have a [] method in Proc that achieves similar effect but it doesn't look like a method call. There's also a dotted syntax hello.("World") but it also looks a little awkward and the dot is easy to forget.

It's probably a bit late for Ruby 4, but I though it's a good opportunity to introduce a potentially big change.

[cheba (Alexander Mankuta)]

• Tracker changed from Bug to Feature
• Backport deleted (3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN)