Feature #7414: Now that const_get supports "Foo::Bar" syntax, so should const_defined?.

• Status: Closed
• Priority: Normal
• Assignee: tenderlovemaking (Aaron Patterson)
• Target version: 2.1.0

[robertgleeson (Robert Gleeson)]

class Foo
end
Object.const_get "Object::Foo" => Foo
Object.const_defined? "Object::Foo" => NameError (expected true).

[robertgleeson (Robert Gleeson)]

I realise defined? with a constant works just as well but this is about API consistency.
I'd expect const_get & const_defined? to support the same syntax ("Object::Foo").

[mame (Yusuke Endoh)]

• Status changed from Open to Assigned
• Assignee set to tenderlovemaking (Aaron Patterson)

Aaron, can you fix it easily?

--
Yusuke Endoh [e-mail]

[sferik (Erik Michaels-Ober)]

I also noticed this inconsistency. It seems very odd to have different behavior for Module#const_get and Module#const_defined?. I hope it's possible to get this change into 2.0.0. It's been a while since I've written any C but I'd be happy to contribute failing specs if that would be helpful.

[benolee (Ben Holley)]

I have been working on a patch, but I have some questions about expected behavior.

In the case when the parent is missing, for example:

# Foo is missing
Object.const_defined?("Foo::Bar")

should it return false? Or raise NameError for "Foo"? Or call Object.const_missing(:Foo)?

Second, in the case when the parent is not a Module or Class, for example:

Foo = Object.new
Object.const_defined?("Foo::Bar")

should it return false? Or raise error "Foo is not a class/module"?

[nobu (Nobuyoshi Nakada)]

I vote for false in both cases, like defined? operator.

[ko1 (Koichi Sasada)]

aaron, could you continue this discussion?

[ko1 (Koichi Sasada)]

• Target version changed from 2.0.0 to 2.1.0

[nobu (Nobuyoshi Nakada)]

• Status changed from Assigned to Closed
• % Done changed from 0 to 100

This issue was solved with changeset r44194.
Robert, thank you for reporting this issue.
Your contribution to Ruby is greatly appreciated.
May Ruby be with you.

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object.c: nested path const_defined?

• object.c (rb_mod_const_defined): support nested class path as well as const_get. [Feature #7414]