class Opal::Nodes::ResBodyNode

def compile
  push "if ("
  rescue_classes.each_with_index do |cls, idx|
    push ', ' unless idx == 0
    call = s(:call, cls, :===, s(:arglist, s(:js_tmp, '$err')))
    push expr(call)
  end
  # if no classes are given, then catch all errors
  push "true" if rescue_classes.empty?
  push ") {"
  if variable = rescue_variable
    variable[2] = s(:js_tmp, '$err')
    push expr(variable), ';'
  end
  line process(rescue_body, @level)
  line "}"
end

def rescue_body
  body || s(:nil)
end

def rescue_classes
  classes = args.children
  classes.pop if classes.last and classes.last.type != :const
  classes
end

def rescue_variable
  variable = args.last
  if Sexp === variable and [:lasgn, :iasgn].include?(variable.type)
    variable.dup
  end
end