From: ara.t.howard@...
Date: 2006-10-21T13:41:26+09:00
Subject: Re: break from block

On Sat, 21 Oct 2006, Farrel Lifson wrote:

> On 20/10/06, Robert Klemme <shortcutter@googlemail.com> wrote:
>> On 20.10.2006 16:37, Farrel Lifson wrote:
>> > I'm just trying to optimise some code and I was wondering if doing
>> >  block = lambda{|i| #processing; if i > 5; break}
>> >  n.times &block
>> > would be any faster than doing it directly.
>> 
>> I do not know a single case where the lambda variant is faster than the
>> direct block variant.  AFAIK that's because of the conversion that
>> occurs.  The advantage of the lambda variant is rather that you can
>> store the block away and reuse it multiple times.
>> 
>> Regards
>> 
>>         robert
>
>> From my informal benchmarking there's a very slight constant speedup
> of about 1s for my program.

what version are you running?  your original code works fine here:

   harp:~ > cat a.rb
   block = lambda{|i| p i; i > 5 ? break : nil}
   42.times &block


   harp:~ > ruby a.rb
   0
   1
   2
   3
   4
   5
   6

   harp:~ > ruby --version
   ruby 1.8.4 (2005-12-01) [i686-linux]

   harp:~ > uname -srm
   Linux 2.4.21-47.EL i686

   harp:~ > cat /etc/redhat-release
   Red Hat Enterprise Linux WS release 3 (Taroon Update 8)

can you show an actual error?

-a
-- 
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