compose

compose.rb

# lambda/proc ver
class Proc
  def self.compose(f, g)
    lambda {|*args| f[g[*args]] }
  end 
  
  def <<(g)
    Proc.compose(self,g)
  end 
 
  def <=(*args)
    self[*args]
  end 
end 
 
unlines = lambda{|seq| seq.join("\n") }
sort = lambda{|seq| seq.sort }
lines = lambda{|str| str.split("\n") }
putStr = lambda{|str| puts str}
 
str = ARGV.join("\n")
 
putStr << unlines << sort << lines <= str 
 
# method ver                                                                                                                                                                                                                                                                                                                
class Method
  def <<(g)
    Proc.compose(self,g)
  end 
 
  def <=(*args)
    self[*args]
  end 
end 
 
def unlines(seq)
  seq.join("\n")
end 
 
def sort(seq)
  seq.sort
end 
 
def lines(str)
  str.split("\n")
end 
 
def putStr(str)
  puts str 
end 
 
method(:putStr) << method(:unlines) << method(:sort) << method(:lines) <= str 

1.8で使いたい場合はProc#[]をProc#callにする必要がある。