From: SASADA Koichi <ko1@...>
Date: 2008-10-22T02:54:15+09:00
Subject: [ruby-core:19421] Re: rb_errinfo() vs rb_rubylevel_errinfo()

Hi,

SASADA Koichi wrote:
> I missed.  $! looking rb_thread_t#errinfo.

missed again.

$! looking local variable, but not "e".

See bellow.  #$! is special local variable to store errinfo.  At
first on an exception handler (rescue in <main>), doing "e = #$!".

> # ----------------------------------------------------------------------
> # target program:
> # ----------------------------------------------------------------------
> begin
> rescue => e
> end
> # ----------------------------------------------------------------------
> # disasm result:
> # ----------------------------------------------------------------------
> == disasm: <RubyVM::InstructionSequence:<main>@../trunk/test.rb>========
> == catch table
> | catch type: rescue st: 0002 ed: 0003 sp: 0000 cont: 0004
> == disasm: <RubyVM::InstructionSequence:rescue in <main>@../trunk/test.rb>
> local table (size: 2, argc: 0 [opts: 0, rest: -1, post: 0, block: -1] s0)
> [ 2] #$!
> 0000 putobject        StandardError                                   (   2)
> 0002 getdynamic       #$!, 0
> 0005 send             :===, 1, nil, 0, <ic>
> 0011 branchunless     20
> 0013 getdynamic       #$!, 0                                          (   3)
> 0016 setlocal         e                                               (   2)
> 0018 putnil                                                           (   3)
> 0019 leave                                                            (   2)
> 0020 getdynamic       #$!, 0
> 0023 throw            0
> | catch type: retry  st: 0003 ed: 0004 sp: 0000 cont: 0002
> |------------------------------------------------------------------------
> local table (size: 2, argc: 0 [opts: 0, rest: -1, post: 0, block: -1] s1)
> [ 2] e
> 0000 trace            1                                               (   1)
> 0002 putnil                                                           (   2)
> 0003 nop                                                              (   1)
> 0004 leave                                                            (   2)
> # ----------------------------------------------------------------------

-- 
// SASADA Koichi at atdot dot net