From: ts <decoux@...>
Date: 2008-04-23T18:25:35+09:00
Subject: Re: Performance on method dispatch for methods defined via define_method

Robert Dober wrote:
> basically I mean that IS.compile("def a; 42 end") ==
> IS.compile("define_method :a do 42 end").

 Well you can do it like me

vgs% ./ruby -e 'puts VM::InstructionSequence.compile("def a() 12; end").disasm'
== disasm: <ISeq:<compiled>@<compiled>>=================================
0000 putnil                                                           (   1)
0001 definemethod     :a, a, 0
0005 putnil           
0006 leave            
== disasm: <ISeq:a@<compiled>>==========================================
0000 putobject        12                                              (   1)
0002 leave            
vgs% 

vgs% ./ruby -e 'puts VM::InstructionSequence.compile("define_method :a do 12; end").disasm'
== disasm: <ISeq:<compiled>@<compiled>>=================================
== catch table
| catch type: break  st: 0000 ed: 0009 sp: 0000 cont: 0009
|------------------------------------------------------------------------
0000 putnil                                                           (   1)
0001 putobject        :a
0003 send             :define_method, 1, block in <compiled>, 8, <ic>
0009 leave            
== disasm: <ISeq:block in <compiled>@<compiled>>========================
== catch table
| catch type: redo   st: 0000 ed: 0002 sp: 0000 cont: 0000
| catch type: next   st: 0000 ed: 0002 sp: 0000 cont: 0002
|------------------------------------------------------------------------
0000 putobject        12                                              (   1)
0002 leave            
vgs% 


 You really think that it exist a big difference *at compile 
 time* ?

Guy Decoux