From: "fxn (Xavier Noria) via ruby-core" <ruby-core@...>
Date: 2023-03-15T23:50:57+00:00
Subject: [ruby-core:112909] [Ruby master Feature#19520] Support for `Module.new(name)` and `Class.new(superclass, name)`.

Issue #19520 has been updated by fxn (Xavier Noria).


This is a long thread, I was not aware of it.

Let me say that nobody can assume from the name of a class or module that the corresponding constant exists. Class and module objects get their name when they are first assigned to a constant, and the `class` and `module` keywords are in part constant assignments. We all know this.

We also know the coupling ends there. These entities ar highly decoupled in Ruby by design. I can have `C = Class.new; c = C; remove_const :C`, and the class in `c` is no longer reachable through the constant after its name. If a Ruby programmer expects that, they have to revise that expectaction because it is just baseless.

----------------------------------------
Feature #19520: Support for `Module.new(name)` and `Class.new(superclass, name)`.
https://bugs.ruby-lang.org/issues/19520#change-102426

* 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
```



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