Vidul Nikolaev Petrov

nil == false => false
nil.nil?        => true
false.nil?     => false
true.nil?      => false
 
if !nil && !false
  puts 'true'
end
 
if nil.nil? && !true.nil?
  puts 'true'
end
 
>> TrueClass.ancestors
=> [TrueClass, Object, Kernel]
>> FalseClass.ancestors
=> [FalseClass, Object, Kernel]
>> NilClass.ancestors
=> [NilClass, Object, Kernel]

alias _rmdir_empty='rmdir * 2>/dev/null'

mt = Array.new(10) { |e| Hash.new { |h,k| h[k] = k * e } }
 
mt[1][2] => 2
mt[2][2] => 4
mt[5][4] => 20
mt[9][5] => 45

# decimal to binary
alias d2b='ruby -e "puts ARGV.first.to_i.to_s(2)"'
# decimal to hexademical
alias d2h='ruby -e "puts ARGV.first.to_i.to_s(16)"'
# decimal to octal
alias d2o='ruby -e "puts ARGV.first.to_i.to_s(8)"'
 
# binary to decimal
alias b2d='ruby -e "puts eval(%q|0b| + ARGV.first)"'
# binary to hexademical
alias b2h='ruby -e "puts eval(%q|0b| + ARGV.first).to_s(16)"'
# binary to octal
alias b2o='ruby -e "puts eval(%q|0b| + ARGV.first).to_s(8)"'
 
# hexademical to decimal
alias h2d='ruby -e "puts eval(%q|0x| + ARGV.first)"'
# hexademical to binary
alias h2b='ruby -e "puts eval(%q|0x| + ARGV.first).to_s(2)"'
# hexademical to octal
alias h2o='ruby -e "puts eval(%q|0x| + ARGV.first).to_s(8)"'
 
# octal to decimal
alias o2d='ruby -e "puts eval(%q|0o| + ARGV.first)"'
# octal to binary
alias o2b='ruby -e "puts eval(%q|0o| + ARGV.first).to_s(2)"'
# octal to hexademical
alias o2h='ruby -e "puts eval(%q|0o| + ARGV.first).to_s(16)"'

require 'rubygems'
require 'google_translate'
 
tr = Google::Translate.new
 
# from English to German
tr.translate :from => "en", :to => "de", :text => "Hello, World!"
 => Hallo, Welt!
 
# from English to Spanish
tr.translate :from => "en", :to => "es", :text => "Hello, World!"
 => Hola, Mundo!
 
# WWW::Mechanize constructor usage
tr = Google::Translate.new { |agent| agent.user_agent_alias = 'Mac Safari' }

require 'benchmark'
 
n = 1_000_000
s = " : : : "
 
Benchmark.bm do |x|
  x.report("tr:")   { n.times{ s.tr(":", ";") } }
  x.report("tr_s:") { n.times{ s.tr_s(":", ";") } }
  x.report("gsub:") { n.times{ s.gsub(":", ";") } }
end

agent = WWW::Mechanize.new
  agent.post("http://translate.google.com/translate_t",
    "sl" => "bg",
    "tl" => "ja",
    "text" => "Здравей, свят!").search("#result_box").inner_html

"a".upto("z"){ |i| puts i }

a = String.new "a"
0.upto(0){ p a }
1.upto(25){ p a.next! }

("a".."z").each{ |e| puts e }