class ERB

def def_class(superklass=Object, methodname='result')

print MyClass.new('foo', 123).render()
MyClass = erb.def_class(MyClass_, 'render()')
erb.filename = filename
erb = ERB.new(File.read(filename))
filename = 'example.rhtml' # @arg1 and @arg2 are used in example.rhtml
end
end
@arg1 = arg1; @arg2 = arg2
def initialize(arg1, arg2)
class MyClass_
example:

Define unnamed class which has _methodname_ as instance method, and return it. 
def def_class(superklass=Object, methodname='result')
  cls = Class.new(superklass)
  def_method(cls, methodname, @filename || '(ERB)')
  cls
end