68-26-171-229:rubinius brian$ shotgun/rubinius describe test.rb 
Sexp:
[:block,
 [:newline, 1, "test.rb", [:lasgn, :obj, [:call, [:const, :Object], :new]]],
 [:newline,
  3,
  "test.rb",
  [:call, [:lvar, :obj, 0], :is_a?, [:array, [:const, :Array]]]],
 [:newline,
  4,
  "test.rb",
  [:call, [:lvar, :obj, 0], :kind_of?, [:array, [:const, :Array]]]],
 [:newline,
  5,
  "test.rb",
  [:call, [:lvar, :obj, 0], :__kind_of__, [:array, [:const, :Array]]]]]

Bytecode:
0000:  push_const                 :Object
0002:  send_method                #<SendSite:0x101 name=new hits=0 misses=0>
0004:  set_local                  :obj
0006:  pop                        
0007:  push_const                 :Array
0009:  push_local                 :obj
0011:  send_stack                 #<SendSite:0x131 name=is_a? hits=0 misses=0>, 1
0014:  pop                        
0015:  push_const                 :Array
0017:  push_local                 :obj
0019:  send_stack                 #<SendSite:0x159 name=kind_of? hits=0 misses=0>, 1
0022:  pop                        
0023:  push_const                 :Array
0025:  push_local                 :obj
0027:  kind_of                    
0028:  pop                        
0029:  push_true                  
0030:  sret