forth ideas (in crystal)

forth_ideas.cr

class Stack
  def initialize
    @contents = [] of Int32
  end
    
  def pop
    @contents.pop()
  end
  
  def push(value)
    @contents << value
  end
  
  def peek
    @contents[-1]
  end
  
  def height
    @contents.size
  end
end

data = Stack.new

stack_add = -> { data.push(data.pop() + data.pop()) }

dictionary = Hash{"add" => stack_add}

data.push(2)
data.push(3)

dictionary["add"].call()

puts data.peek()
puts data.height