From: "zverok (Victor Shepelev) via ruby-core" <ruby-core@...>
Date: 2025-12-03T19:53:38+00:00
Subject: [ruby-core:124012] [Ruby Misc#21762] Box: Inspect improvements

Issue #21762 has been reported by zverok (Victor Shepelev).

----------------------------------------
Misc #21762: Box: Inspect improvements
https://bugs.ruby-lang.org/issues/21762

* Author: zverok (Victor Shepelev)
* Status: Open
----------------------------------------
1\. Currently, `Ruby::Box` provides an `#inspect` method, and its output is reasonably short yet mysterious:
```ruby
Ruby::Box.new
#=> #<Namespace:3,user,optional>
```
First, it uses old `Namespace` name instead of `Ruby::Box`. Next, I am not sure how to interpret everything that goes after the class name (reading through `#inspect` [code](https://docs.ruby-lang.org/en/master/Ruby/Box.html#method-i-inspect) gives some insight, bug I am still unsure what should "user" or "optional" mean).

2\. Box doesn't redefine `#to_s`, which leads to this:

```ruby
b = Ruby::Box.new
puts b
# #<#<Class:0x0000788614d88340>:0x000078861444b0e8>

# or, more realistically:
raise "Something bad happened in #{b}"
# Something bad happened in #<#<Class:0x0000788614d88340>:0x000078861444b0e8> (RuntimeError)
```

I think that making `#to_s` an alias to `#inspect` would be reasonable.

3\. In Ruby 4.0.0-preview2, `#inspect` of nested classes was prefixed with `#to_s` of the box. 

```ruby
b.require('cgi')
b.eval('CGI')
#=> #<#<Class:0x00007750c2e9d0d8>:0x00007750c20050c0>::CGI
```

While with the current `#to_s` it looked weird, if (2) is fixed, it could become quite reasonable (i.e. if it looked like `<Ruby::Box:1>::CGI`).

In the current master, the behavior had changed:
```ruby
b.require('cgi')
b.eval('CGI')
#=> CGI
```

Which is confusing, because it looks like a constant that can be referred from the outer scope, but it is not:
```ruby
CGI
# uninitialized constant CGI (NameError)
require 'cgi'
CGI == b.eval('CGI') #=> false
```

Can we reconsider changing inspect back to scoped one? I understand there might be some downsides (like if some library checks the literal value of `#inspect` of something to make decisions about the class identity), but as `Box` is experimental anyway, now might be a good time to investigate upsides/downsides?..

4\. That's a completely optional proposal, but if the `#inspect`/`#to_s` improvements would be made, can we consider (if it is possible) respecting the Box instance being assigned to a constant? Like it happens with dynamically-generated classes:

```ruby
c = Class.new
#=> #<Class:0x00007ec030697ef8>
C = c  # class receives a name
c
#=> C
```

Together with my point (3), this might lead to pretty clear naming conventions visible in logs and other places, like `OldAPI::SomeLibrary` (where `OldAPI` is a name of a Box, and `SomeLibrary` is loaded there).



-- 
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