# File lib/ruby2ruby.rb, line 670
  def process_op_asgn2(exp)
    # [[:lvar, :c], :var=, :"||", [:lit, 20]]
    lhs = process(exp.shift)
    index = exp.shift.to_s[0..-2]
    msg = exp.shift

    rhs = process(exp.shift)

    "#{lhs}.#{index} #{msg}= #{rhs}"
  end