[ot][spam][crazy][puzzle?][spam][crazy]

[Undescribed Horrific Abuse, One Victim & Survivor of Many]

# wonder stuff
class Expr:
  def __init__(self, name, call, inverse = None):
    self.name = name
    self.call = call
    if inverse is not None:
      self.inverse = inverse
      inverse.inverse = self
      # note there can be more than one inverse; is more general
      # to think of inputs and outputs together and describe how they swizzle

plus = Expr('+', lambda x, y: x + y)
minus = Expr('-', lambda x, y: x - y, plus)

class Const(Expr):