From: dblack@...
Date: 2007-08-04T07:45:53+09:00
Subject: Re: binding - how to explain it?

Hi --

On Sat, 4 Aug 2007, Giles Bowkett wrote:

>>> defining context. But it seems to contradict what David Black posted
>>> earlier, and I saw the same thing in my own irb.
>>
>> I don't think it contradicts my example; I'm evaluating "puts a"
>> inside a method where a has not been defined.  Morton's examples
>> either use the top-level binding explicitly, or set an a variable in
>> the method.  My example doesn't do either, so the top-level assignment
>> to a is essentially playing no role.
>
> but why in Morton's code does the method's call to binding result in
> the same binding as TOPLEVEL_BINDING, when in your code calling
> binding from a method doesn't result in getting the var a which seems
> to live in the top-level binding?

It doesn't; there's a parameter 'a'.  Here's Morton's example again:

def x(a)
   eval(DATA.read, binding)
end

x(42)

__END__
puts a

Inside the method, a is set to 42, and in the context of that binding,
"puts a" is executed.


David

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