module Kernel

  Ruby♯ = '☠ ☢ ☹'

  alias λ proc
  alias ⚠ raise

  #Arabic-Indic digits
  #There's some RTL stuff going on here, but they're actually
  #in the right order
  %w(١ ٢ ٣ ٤ ٥ ٦ ٧ ٨ ٩).each_with_index do |digit,index|
    define_method digit do |*nxt|
      this = index+1
      nxt = nxt.empty? ? nil : nxt.first
      if nxt
        this * (10 ** (1 + (Math.log10(nxt).floor))) + nxt
      else
        this
      end
    end
  end

  #Roman
  %w(Ⅰ Ⅴ Ⅹ Ⅼ Ⅽ Ⅾ Ⅿ ↁ ↂ).zip([1,5,10,50,100,500,1000,5000,10000]).each do |numeral,value|
    define_method numeral do |*nxt|
      value + nxt.inject(0){|s,n| s+n }
    end
  end

  #Sum args
  def ∑(*args)
    args.inject(0){|sum,arg| sum+arg }
  end

  #Sq. root
  def √(n)
    Math.sqrt(n)
  end

  def ∞
    1/0.0
  end

  def π
    Math::PI
  end
  alias ℼ π

  def Ω
    0.5671432904097838729999686622
  end

  def ε
    Float::EPSILON
  end

  def ␀ #NUL
    nil
  end

  def ♻
    GC.start
  end

end

class Proc
  alias ❪❫ call
end

#These probably belong in Set instead of Array
class Array

  alias ∋ include?
  alias ∩ &
  alias ∪ |

  def ∌(element)
    !include?(element)
  end
  
  def ⊂(array)
    size < array.size && all?{|e| array.include?(e) }
  end

  def ⊅(array)
    size > array.size && array.all?{|e| include?(e) }
  end
  
  def ⊆(array)
    all?{|e| array.include?(e) }
  end

  def ⊇(array)
    array.all?{|e| include?(e) }
  end

  def ⊄(array)
    !⊂(array)
  end

  def ⊅(array)
    !⊂(array)
  end

  def ⊈(array)
    !⊆(array)
  end

  def ⊉(array)
    !⊇(array)
  end

  def ∑
    inject(0){|sum,n| sum+n }
  end

end

[Fixnum,Float].each do |klass|

  klass.class_eval do

    alias ⩽ <=
    alias ⩾ >=

  end

end