def after_and_asgn
      variable = variable_stack.pop.first
      value    = value_stack.pop.first

      conditional_assignment(variable, value)
    end
def after_and_asgn
      variable = variable_stack.pop.first
      value    = value_stack.pop.first

      conditional_assignment(variable, value)
    end
Processes an `and` assignment in the form of `variable &&= value`.