some ruby 2.0 features

argumentos_nomeados.rb

# ruby 1.9 - Argumentos Ordenados
def params_1_9(name, age)
  name = args[:name]
  age  = args[:age]

  puts name
  puts age
end

# ruby 2.0 - Argumentos Nomeados
def params_2_0(name: "nome default", age: 20)
  puts name
  puts age
end

params_2_0 age: 12, name: "goten"

bsearch.rb

# ruby 2.0
array = [0, 4, 7, 10, 12]

puts array.bsearch {|x| x >= 6 }

dir.rb

# ruby 1.9
puts File.dirname(File.realpath(__FILE__))

# ruby 2.0
puts __dir__

double_splat.rb

def double_splat(name: "nome default", age: 20, **catched)
  puts name
  puts age
  puts catched
end

double_splat name: "goku", age: 44, level: "saiyajin 7", ki: "890"

p method(:double_splat).parameters

dtrace.txt

Wikipedia

DTrace can be used to get a global overview of a running system,
such as the amount of memory, CPU time, filesystem and network resources
used by the active processes.
It can also provide much more fine-grained information,
such as a log of the arguments with which a specific function is being called,
 or a list of the processes accessing a specific file.

Linguagens:
Assembly language, C, C++, Java, JavaScript, Perl, PHP, Python, Shell e RUBY :DDD

Infos sobre:
Fluxo de execução
Análise performance em tempo de execução
Memória, kernel,..
Garbage collector


Google Talk sobre DTrace: http://www.youtube.com/watch?v=TgmA48fILq8&feature=gv
===================================================================================================

[root@dn10 dtrace]$cat rb_funcalls.d
#!/usr/sbin/dtrace -Zqs
 /\*
 \* How do you invoke this script?
 \* Use dtrace -xbufsize=40m -Zqs rb_funcall.d -c "ruby my_arg1 my_arg2"
 \* Where "ruby" is DTrace enabled.
 \*/


 /\*
 \* Thread local variable to
 \* store the indentation level
 \* during/after a function call.
 \*/
 self int indent;

 dtrace:::BEGIN
 {
    printf("Starting to trace\\n");
 }

 ruby\*:::function-entry
 {
    /\*
    \* To ensure that we capture function
    \* entries and returnes made by a thread
    \* in order.
    \*/
    self->thread = 1;
 }

 ruby\*:::function-entry
 /self->thread/
 {
    self->indent += 2;
    printf("%\*s", self->indent, " ");
    printf("=> %s->%s\\n", copyinstr(arg0), copyinstr(arg1));
 }

 ruby\*:::function-return
 /self->thread/
 {
   printf("%\*s", self->indent, " ");
   printf("<= %s->%s\\n", copyinstr(arg0), copyinstr(arg1));
   self->indent -= 2;
 }

 dtrace:::END
 {
   printf("Finished tracing\\n");
 }
[root@dn10 dtrace]$

[root@dn10 dtrace]$cat /tmp/hello.rb
message = String.new("Hello World")
puts message
[root@dn10 dtrace]$

[root@dn10 dtrace]$dtrace -xbufsize=40m -Zqs rb_funcalls.d  -c "ruby /tmp/hello.rb"
Starting to trace
Hello World
  => Class->new
    => String->initialize
    <= String->initialize
  <= Class->new
  => Object->puts
    => IO->write
    <= IO->write
    => IO->write
    <= IO->write
  <= Object->puts
Finished tracing

method_extend.rb

class Time
  def melhor_do_br
    puts "Fluminense"
  end
end

Time.new.melhor_do_br

class Time
  method_for_change = instance_method :melhor_do_br

  define_method :melhor_do_br do
    method_for_change.bind(self).call
    puts "será melhor da américa em 2013"
  end
end

Time.new.melhor_do_br

method_extend_by_alias.rb

class Time
  def melhor_do_br
    puts "Fluminense"
  end
end

Time.new.melhor_do_br

class Time
  alias_method :fodão_do_br, :melhor_do_br

  def melhor_do_br
    fodão_do_br
    puts "será melhor da américa em 2013"
  end
end

Time.new.melhor_do_br

outras_coisas.txt

* Expressões regulares com onigumo

* Refinements (restrição da total abertura de classes do ruby, ainda não está 100% quanto sua implementação)

* Novos métodos da classe Enumerators

* Mais uma porrada de coisa que a gente provavelmente não precisa saber agora

* Ler post do Nando!

* Documento com todas as modificações https://github.com/ruby/ruby/blob/ruby_2_0_0/NEWS

* Instalação

  cd ~/.rbenv/plugins/ruby-build
  git pull
  rbenv install 2.0.0-p0
  rbenv local 2.0.0-p0

symbols_array.rb

# ruby 1.9
p %w[simba timão pumba]

# ruby 2.0
p %i[simba timão pumba]

king = :mufasa
p %I[simba timão pumba #{king}]


puts __ENCODING__
# ruby 1.9 era US-ASCII

to_h.rb

# to_h no classe OpenStruct
require "ostruct"

warrior = OpenStruct.new(name: "goku", level: "saiyajin 7")

puts warrior
puts warrior.to_h
w = warrior.to_h
puts w[:name]

# to_h no classe Struct
Warrior = Struct.new(:name, :level)
warrior2 = Warrior.new("gohan", "saiyajin 2")

puts warrior2
puts warrior2.to_h

warnings.rb

#ruby -c -w
var1 = 1
var2 = 2

_var3 = 3

puts var1