[ruby-core:112845] [Ruby master Feature#19520] Support for `Module.new(name)` and `Class.new(superclass, name)`.

10 Mar 2023

      Issue #19520 has been updated by Eregon (Benoit Daloze).

ioquatix (Samuel Williams) wrote in #note-12:
...
I don't understand this argument at all. The assumptions are already broken by the trivial examples already given.
They are not or very rarely broken in practice, that matters a lot.
...
=> "#<Module:0x00007f4ea0f5d160>::Bar"
The name given here is not valid.
That's fine, this is easy to recognize there an anonymous module in there, there is no confusion.
Unlike a `Foo::Bar` name with this feature and yet never having a `Foo` constant defined on Object.

----------------------------------------
Feature #19520: Support for `Module.new(name)` and `Class.new(superclass, name)`.
https://bugs.ruby-lang.org/issues/19520#change-102357

* Author: ioquatix (Samuel Williams)
* Status: Open
* Priority: Normal
----------------------------------------
See <https://bugs.ruby-lang.org/issues/19450> for previous discussion and motivation.

[This proposal](https://github.com/ruby/ruby/pull/7376) introduces the `name` parameter to `Class.new` and `Module.new`:

```ruby
Class.new(superclass, name)
Module.new(name)
```

As a slight change, we could use keyword arguments instead.

## Example usage

The current Ruby test suite has code which shows the usefulness of this new method:

```ruby
  def labeled_module(name, &block)
    Module.new do
      singleton_class.class_eval {
        define_method(:to_s) {name}
        alias inspect to_s
        alias name to_s
      }
      class_eval(&block) if block
    end
  end
  module_function :labeled_module

  def labeled_class(name, superclass = Object, &block)
    Class.new(superclass) do
      singleton_class.class_eval {
        define_method(:to_s) {name}
        alias inspect to_s
        alias name to_s
      }
      class_eval(&block) if block
    end
  end
  module_function :labeled_class
```

The updated code would look like this:

```ruby
  def labeled_module(name, &block)
    Module.new(name, &block)
  end

  def labeled_class(name, superclass = Object, &block)
    Class.new(superclass, name, &block)
  end
  module_function :labeled_class
```

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