=begin
Ruby 1.9でRange#include?がものすごい遅いようです。

require 'benchmark'
RUBY_VERSION # => "1.8.7"
Benchmark.bmbm(10) do |b|
n = 100
b.report("include") { n.times{ ("an".."ruby").include? "elf" }}
b.report("between") { n.times{ "elf".between?("an","ruby") }}
end

>> Rehearsal ---------------------------------------------¶

>> include 0.000000 0.000000 0.000000 ( 0.000278)¶

>> between 0.000000 0.000000 0.000000 ( 0.000113)¶

>> ------------------------------------ total: 0.000000sec¶

>>¶

>> user system total real¶

>> include 0.000000 0.000000 0.000000 ( 0.000233)¶

>> between 0.000000 0.000000 0.000000 ( 0.000113)¶

require 'benchmark'
RUBY_VERSION # => "1.9.0"
Benchmark.bmbm(10) do |b|
n = 100
b.report("include") { n.times{ ("an".."ruby").include? "elf" }}
b.report("between") { n.times{ "elf".between?("an","ruby") }}
end

>> Rehearsal ---------------------------------------------¶

>> include 0.420000 0.000000 0.420000 ( 0.417621)¶

>> between 0.000000 0.000000 0.000000 ( 0.000116)¶

>> ------------------------------------ total: 0.420000sec¶

>>¶

>> user system total real¶

>> include 0.420000 0.000000 0.420000 ( 0.422576)¶

>> between 0.000000 0.000000 0.000000 ( 0.000120)¶

=end