From: Vincent Fourmond <vincent.fourmond@9online.fr>
Date: 2007-01-10T05:53:59+09:00
Subject: Re: String performance

George Palmer wrote:
> Guys a quick performance question - Is either one of the following more
> efficient than the other?  I'm guessing they're in this order:
> 
> 'a' + x + 'b'
> "a" + x + "b"
> "a#{x}b"

  Exactly the opposite:


21:52 vincent@tanyaivinco ~/Prog/Ruby ruby rt_7.rb
      user     system      total        real
  0.010000   0.000000   0.010000 (  0.009087)
  0.010000   0.000000   0.010000 (  0.008774)
  0.000000   0.000000   0.000000 (  0.004621)

rt_7.rb is

require 'benchmark'

n = 5000
c = "stuff"
Benchmark.bm do |x|
  x.report { n.times {'a' + c + 'b'}}
  x.report { n.times {"a" + c + "b"}}
  x.report { n.times {"a#{c}b"}}
end

  If you're looking for a performance question, Benchmark is nearly
always your answer.

	Vince


-- 
Vincent Fourmond, PhD student
http://vincent.fourmond.neuf.fr/