From: dblack@...
Date: 2006-12-13T01:57:24+09:00
Subject: Re: How do I catch a missing method on a passed block?

Hi --

On Wed, 13 Dec 2006, J2M wrote:

>
> dblack@wobblini.net wrote:
>
>>>>> What made this sweet for me was turning the &block into a lambda let me
>>>>> return the result from the instance_eval to bar where other solutions
>>>>> kept them in scope of the &block.
>>>>
>>>> But the block *is* a lambda :-)  That's what the &block argument does:
>>>> it captures the code block in an object and assigns a variable to it.
>>>
>>> But without the lambda it is a raw proc that doesn't return the result
>>> of the method - from what I understand from page 344 of Pickaxe. I
>>> tried without and didn't get the result passed back from
>>> method_missing, but I will now test that again :-)
>>
>> You may be right; I didn't demo it because I couldn't figure out
>> exactly what code I needed to add :-)  You may be hitting one of the
>> Proc/proc/lambda/block difference things.
>
> You are right David, I chopped the lambda and it still works ;-/
>
> I don't see how to get rid of the class variable as I am building a
> hash from the repeated call to method_missing inside the block then
> returning that through the instance_eval, if I don't use the class
> variable, I will only get the result of the last call to
> method_missing?

I'd have to see the current version of the code to be sure, but
define_method gives you a closure, so if you have a local variable
outside it, that variable will be captured.  Or maybe an instance
variable.  Can you post what you've currently got?


David

-- 
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