[ruby-core:71640] [Ruby trunk - Bug #11718] Constant access on `nil`

Issue #11718 has been updated by Elia Schito.


looks like it's somehow intended behavior

https://github.com/ruby/ruby/blob/trunk/insns.def#L179-L190

      /**
        @c variable
        @e
         Get constant variable id. If klass is Qnil, constants
         are searched in the current scope. If klass is Qfalse, constants
         are searched as top level constants. Otherwise, get constant under klass
         class or module.
        @j 定数 id の値を得る。
         klass が Qnil なら、そのスコープで得られる定数の値を得る。
         Qfalse なら、トップレベルスコープを得る。
         それ以外なら、klass クラスの下の定数を得る。
       */

apparently introduced here: https://github.com/ruby/ruby/commit/d84f9b16946bca06ce0557ebe99152d7d445c9ec to resolve bug #10943

----------------------------------------
Bug #11718: Constant access on `nil`
https://bugs.ruby-lang.org/issues/11718#change-55042

* Author: Vais Salikhov
* Status: Open
* Priority: Normal
* Assignee: 
* ruby -v: ruby 2.2.3p173 (2015-08-18 revision 51636) [x86_64-linux]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN
----------------------------------------
It is possible to access top-level constants by doing `nil::CONSTANT`, which looks like a bug [according to Matz](https://github.com/opal/opal/issues/1197#issuecomment-158078778). Here are a couple of examples:

```
$ ruby -ve "Foo = 123; p nil::Foo"
ruby 2.2.3p173 (2015-08-18 revision 51636) [x86_64-linux]
123
```

```
$ ruby -ve "class A; Foo = 456; end; p nil::A::Foo"
ruby 2.2.3p173 (2015-08-18 revision 51636) [x86_64-linux]
456
```

Thanks!



-- 
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