From: Robert Klemme <bob.news@...>
Date: 2006-01-08T01:13:00+09:00
Subject: Re: Iterator Fu Failing Me

Bob Hutchison <hutch@recursive.ca> wrote:
> 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

Because this won't return the proper value from the block.  You need at 
least to add a line with "result" after the #find. :-)  And then it's much 
more inelegant than using #detect. :-)

Kind regards

    robert