From: ts <decoux@...>
Date: 2008-03-25T22:34:00+09:00
Subject: #defined?


 Two small problems with defined?

 * Empty NODE_BEGIN

vgs% ./ruby -ve 'puts VM::InstructionSequence.compile("p defined?(a.a=())").disasm'
ruby 1.9.0 (2008-03-25 revision 15839) [i686-linux]
== disasm: <ISeq:<compiled>@<compiled>>=================================
== catch table
| catch type: ensure st: 0001 ed: 0006 sp: 0001 cont: 0032
== disasm: <ISeq:defined guard in <compiled>@<compiled>>================
0000 putnil           
0001 leave            
|------------------------------------------------------------------------
0000 putnil                                                           (   1)
0001 putnil           
0002 branchunless     32
0004 putobject        true
0006 branchunless     32
0008 putobject        true
0010 branchunless     32
0012 putself          
0013 defined          21, :a, false
0017 branchunless     32
0019 putnil           
0020 send             :a, 0, nil, 24, <ic>
0026 defined          13, :a=, true
0030 jump             33
0032 putnil           
0033 send             :p, 1, nil, 8, <ic>
0039 leave            
vgs% 


 * Don't catch the error

vgs% ./ruby -ve 'def a() end; p defined?(a(1).a)'
ruby 1.9.0 (2008-03-25 revision 15839) [i686-linux]
-e:1:in `<main>': wrong number of arguments (1 for 0) (ArgumentError)
vgs% 

vgs% ./ruby -ve 'def a(x) end; p defined?(a::B)'
ruby 1.9.0 (2008-03-25 revision 15839) [i686-linux]
-e:1:in `<main>': wrong number of arguments (0 for 1) (ArgumentError)
vgs% 


Guy Decoux