From: RichardOnRails <RichardDummyMailbox58407@...>
Date: 2011-05-28T23:00:27+09:00
Subject: Re: Problem in using %:whatever in enumumerations

On May 28, 2:20 am, Victor Deryagin <vderya...@gmail.com> wrote:

Thanks for your response.

> > greek = %w{Alpha Beta Gamma}
> > puts greek.all? { |s| s.length == 5 }              #  (correct)  => false
> > puts greek.all? { |s| (4..5).include? s.length }   #  (correct)  => true
> > puts greek.all?(&:length)                      #  (programmer error)     => true

> ... If that's not what you want (e.g. you need { |s| s.length == 5 }) -
> construct block yourself.

I did construct the block myself in the first couple of examples
(lines 2 & 3) but was searching (in line 4) for another way of
expressing the requirement.

I finally found a way to use a lambda in the following statements in
place of line 4:

lam = lambda { |item, len| item.length == 5 }
puts greek.all? { |s| lam.call(s,5)}			#  (correct)  => false

Of course, the verbosity of this pair of statements is unsatisfying,
so I'm still searching for succinct alternatives.

Best wishes,
Richard