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Feature #5360

BasicObject#binding

Added by Thomas Sawyer almost 5 years ago. Updated almost 4 years ago.

Status:
Feedback
Priority:
Normal
Assignee:
-
[ruby-core:39690]

Description

For meta-programming purposes I think there needs to be a way to get a BasicObject's binding.

History

#1 [ruby-core:39692] Updated by Nobuyoshi Nakada almost 5 years ago

  • Status changed from Open to Feedback

Can you elaborate?

#2 [ruby-core:39695] Updated by Thomas Sawyer almost 5 years ago

Sure. I think the most obvious usecase is with ERB. If I want to strictly control the available interface to an ERB template a subclass of BasicObject is an ideal way to do. But ERB's result method takes a binding. So that's one specific case I've come across, and I am certain there are others given that both BasicObject and binding are very useful devices in the context of meta-programming.

#3 Updated by George Koehler almost 5 years ago

I can get a Binding from a BasicObject like so:

class Cow < BasicObject
Moo = "Moooo!"
def binding
::Kernel.binding
end
end

b = Cow.new.binding
p eval("Moo", b) # => "Moooo!"
p eval("String", b) # raises NameError

This uses the syntax "::Kernel" to access a global constant.

#4 [ruby-core:39757] Updated by Thomas Sawyer almost 5 years ago

On Sep 27, 3:51 pm, George Koehler xkern...@netscape.net wrote:

Issue #5360 has been updated by George Koehler.

I can get a Binding from a BasicObject like so:

 class Cow < BasicObject
   Moo

#5 [ruby-core:49152] Updated by Yusuke Endoh almost 4 years ago

  • Target version set to next minor

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