From: dblack@...
Date: 2006-07-09T04:32:06+09:00
Subject: Re: Sweet Lord!

Hi --

On Sun, 9 Jul 2006, Phil Tomson wrote:

> On 7/8/06, William James <w_a_x_man@yahoo.com> wrote:
>> Daniel Schierbeck wrote:
>> > Why haven't I thought of this before?
>> >
>> >    class Terminal
>> >      include Enumerable
>> >
>> >      def each(&block)
>> >        while input = gets
>> >          block.call(input.chomp)
>> >        end
>> >      end
>>
>>   def each
>>     while input = gets
>>       yield input.chomp
>>     end
>>   end
>
> Equivilent code, actually.  It's a case of "you say tomaTOE I say tomAHto"
> Personally, I tend to prefer the 'block.call' because you explicitly
> say you're passing in a block in the definition of the method, so if
> someone is reading your code they can easily tell that the method
> takes a block.  In the case of yield you might need to read through a
> good bit of code before you find out that the method takes a block.

It does seem that yielding is faster; note the effect of turning the
block into a Proc object:

require 'benchmark'
include Benchmark

n = 100000

def y
end

def b(&block)
end

bm do |x|
   x.report("call") { n.times { b { } } }
   x.report("yield") { n.times { y { } } }
end

# Output:

       user     system      total        real
call  1.860000   0.040000   1.900000 (  2.874001)
yield  0.220000   0.000000   0.220000 (  0.249164)


David

-- 
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