From: Bob Hutchison <hutch@...>
Date: 2006-01-08T01:04:13+09:00
Subject: Re: Iterator Fu Failing Me


On Jan 6, 2006, at 11:36 PM, James Edward Gray II wrote:

> That works.  Now can anyone give me a version of the middle section  
> that doesn't require I call parse?() 50 times?  I want something  
> close to:
>
>   elements = tokens.map do |token|
>     [ClassA, ClassB, ClassC].find { |kind| kind.parse?(token) }
>   end
>
> Except that I want the return result of parse?(), instead of the  
> class that took it.

Why not:

elements = tokens.map do |token|
   result = nil
   [ClassA, ClassB, ClassC].find { |kind| result = kind.parse?(token) }
end


----
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