/fast- event mystery (jsc) | Tech Off

JScript
Way to go.

Hmm, "Specified cast is not valid" error: only when compiled with /fast off.


import System;
import System.Windows.Forms;


Application.Run(new EventTestForm);


class EventTestForm extends Form
{
   function EventTestForm()
   {
      var button : Button = new Button;

      button.Text = "click";

      Controls.Add(button);

      try
      {
         button.add_Click(this.clicky);
      }
      catch(er)
      {
         MessageBox.Show(er.message,"Error!",MessageBoxButtons.OK,MessageBoxIcon.Error);

         MessageBox.Show("clicky is a " + typeof this.clicky);
      }
   }


   function clicky(obj, evt : EventArgs)
   {
      MessageBox.Show("clicky is a " + typeof this.clicky);
   }
}

That's basically this example; strange...

Roobin
My 1303S

Does it make any difference if you move:

Application.Run(new EventTestForm);

to the end of the script?

JScript
Way to go.

Nah, it's global--so the order of Application.Run() makes no difference there.

The problem lies in the parameter of button.add_Click(), which is somehow different when compiled in "slow mode", even though it shows up as a function in either case. Totally confusing...

Sven Groot
You can't have everything; after all, where would you put it?

Could you use ILDASM and post the generated IL code for the function both with and without /fast?

JScript
Way to go.

Hmm, IL text output is identical (according to cmd comp)...

JScript
Way to go.

Double checking, the output is actually different (my mistake); let's see...

JScript
Way to go.

WinDiff:

    // =============================================================


    // =============== GLOBAL FIELDS AND METHODS ===================


    // =============================================================


    // =============== CLASS MEMBERS DECLARATION ===================
    //   note that class flags, 'extends' and 'implements' clauses
    //          are provided here for information only

    .class public auto ansi 'JScript 0'
           extends [Microsoft.JScript]Microsoft.JScript.GlobalScope
    {
      .custom instance void [mscorlib]System.Runtime.CompilerServices.CompilerGlobalScopeAttribute::.ctor() = ( 01 00 00 00 )
      .method public specialname rtspecialname
              instance void .ctor(class [Microsoft.JScript]Microsoft.JScript.GlobalScope A_1) cil managed
      {
        // Code size       14 (0xe)
        .maxstack 3
        IL_0000: ldarg.0
        IL_0001: ldarg.1
        IL_0002: dup
        IL_0003: ldfld      class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.ScriptObject::engine
        IL_0008: call       instance void [Microsoft.JScript]Microsoft.JScript.GlobalScope::.ctor(class [Microsoft.JScript]Microsoft.JScript.GlobalScope,
                                                                                                   class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine)
        IL_000d: ret
      } // end of method 'JScript 0'::.ctor

      .method public instance object 'Global Code'() cil managed
      {
<!     // Code size       176 (0xb0)
<!     .maxstack 7
!>     // Code size       80 (0x50)
!>     .maxstack 3
<-     .locals init (class [Microsoft.JScript]Microsoft.JScript.LateBinding V_0)
        IL_0000: ldarg.0
        IL_0001: ldfld      class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.ScriptObject::engine
        IL_0006: ldarg.0
        IL_0007: call       instance void [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine::PushScriptObject(class [Microsoft.JScript]Microsoft.JScript.ScriptObject)
        IL_000c: ldstr      "System"
        IL_0011: ldarg.0
        IL_0012: ldfld      class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.ScriptObject::engine
        IL_0017: call       void [Microsoft.JScript]Microsoft.JScript.Import::JScriptImport(string,
                                                                                             class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine)
        IL_001c: ldstr      "System.Windows.Forms"
        IL_0021: ldarg.0
        IL_0022: ldfld      class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.ScriptObject::engine
        IL_0027: call       void [Microsoft.JScript]Microsoft.JScript.Import::JScriptImport(string,
                                                                                             class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine)
<!     IL_002c: ldstr      "Run"
<!     IL_0031: newobj     instance void [Microsoft.JScript]Microsoft.JScript.LateBinding::.ctor(string)
<!     IL_0036: stloc.0
<!     IL_0037: ldloc.0
<!     IL_0038: dup
<!     IL_0039: ldarg.0
<!     IL_003a: ldfld      class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.ScriptObject::engine
<!     IL_003f: call       instance class [Microsoft.JScript]Microsoft.JScript.ScriptObject [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine::ScriptObjectStackTop()
<!     IL_0044: castclass [Microsoft.JScript]Microsoft.JScript.IActivationObject
<!     IL_0049: ldstr      "Application"
<!     IL_004e: ldc.i4.0
<!     IL_004f: callvirt   instance object [Microsoft.JScript]Microsoft.JScript.IActivationObject::GetMemberValue(string,
<!                                                                                                                 int32)
<!     IL_0054: dup
<!     IL_0055: call       bool [Microsoft.JScript]Microsoft.JScript.Binding::IsMissing(object)
<!     IL_005a: brfalse    IL_006a
<!
<!     IL_005f: pop
<!     IL_0060: ldtoken    [System.Windows.Forms]System.Windows.Forms.Application
<!     IL_0065: call       class [mscorlib]System.Type [mscorlib]System.Type::GetTypeFromHandle(valuetype [mscorlib]System.RuntimeTypeHandle)
<!     IL_006a: ldarg.0
<!     IL_006b: ldfld      class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.ScriptObject::engine
<!     IL_0070: call       object [Microsoft.JScript]Microsoft.JScript.Convert::ToObject(object,
!>     IL_002c: newobj     instance void EventTestForm::.ctor()
->     IL_0031: dup
!>     IL_0032: ldarg.0
!>     IL_0033: ldfld      class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.ScriptObject::engine
!>     IL_0038: callvirt   instance void [Microsoft.JScript]Microsoft.JScript.INeedEngine::SetEngine(class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine)
!>     IL_003d: call       void [System.Windows.Forms]System.Windows.Forms.Application::Run(class [System.Windows.Forms]System.Windows.Forms.Form)
!>     IL_0042: ldnull
!>     IL_0043: ldarg.0
!>     IL_0044: ldfld      class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.ScriptObject::engine
!>     IL_0049: call       instance class [Microsoft.JScript]Microsoft.JScript.ScriptObject [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine::PopScriptObject()
!>     IL_004e: pop
!>     IL_004f: ret
<-                                                                                        class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine)
<!     IL_0075: stfld      object [Microsoft.JScript]Microsoft.JScript.LateBinding::obj
<!     IL_007a: ldc.i4.1
<!     IL_007b: newarr     [mscorlib]System.Object
<!     IL_0080: dup
<!     IL_0081: ldc.i4.0
<!     IL_0082: newobj     instance void EventTestForm::.ctor()
<!     IL_0087: dup
<!     IL_0088: ldarg.0
<!     IL_0089: ldfld      class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.ScriptObject::engine
<!     IL_008e: callvirt   instance void [Microsoft.JScript]Microsoft.JScript.INeedEngine::SetEngine(class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine)
<!     IL_0093: stelem.ref
<!     IL_0094: ldc.i4.0
<!     IL_0095: ldc.i4.0
<!     IL_0096: ldarg.0
<!     IL_0097: ldfld      class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.ScriptObject::engine
<!     IL_009c: call       instance object [Microsoft.JScript]Microsoft.JScript.LateBinding::Call(object[],
<!                                                                                                 bool,
<!                                                                                                 bool,
<!                                                                                                 class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine)
<!     IL_00a1: pop
<!     IL_00a2: ldnull
<!     IL_00a3: ldarg.0
<!     IL_00a4: ldfld      class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.ScriptObject::engine
<!     IL_00a9: call       instance class [Microsoft.JScript]Microsoft.JScript.ScriptObject [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine::PopScriptObject()
<!     IL_00ae: pop
<!     IL_00af: ret
      } // end of method 'JScript 0'::'Global Code'

    } // end of class 'JScript 0'

    .class public auto ansi serializable EventTestForm
           extends [System.Windows.Forms]System.Windows.Forms.Form
           implements [Microsoft.JScript]Microsoft.JScript.INeedEngine
    {
      .field private notserialized class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine 'vsa Engine'
      .method public specialname rtspecialname
              instance void .ctor() cil managed
      {
<!     // Code size       726 (0x2d6)
<!     .maxstack 31
!>     // Code size       185 (0xb9)
->     .maxstack 11
        .locals init (class [System.Windows.Forms]System.Windows.Forms.Button V_0,
                 object V_1,
                 object V_2,
                 class [Microsoft.JScript]Microsoft.JScript.LateBinding V_3,
<!              class [Microsoft.JScript]Microsoft.JScript.LateBinding V_4,
!>              class [Microsoft.JScript]Microsoft.JScript.LateBinding V_4)
<!              class [Microsoft.JScript]Microsoft.JScript.LateBinding V_5,
<!              class [Microsoft.JScript]Microsoft.JScript.LateBinding V_6,
<!              class [Microsoft.JScript]Microsoft.JScript.LateBinding V_7,
<!              class [Microsoft.JScript]Microsoft.JScript.LateBinding V_8,
<!              class [Microsoft.JScript]Microsoft.JScript.LateBinding V_9,
<!              object V_10,
<!              class [System.Windows.Forms]System.Windows.Forms.Control V_11,
<!              object V_12,
<!              object V_13,
<!              class [System.Windows.Forms]System.Windows.Forms.Control V_14,
<!              object V_15)
        IL_0000: ldarg.0
        IL_0001: call       instance void [System.Windows.Forms]System.Windows.Forms.Form::.ctor()
        IL_0006: ldarg.0
        IL_0007: call       instance void EventTestForm::'.init'()
<!     IL_000c: ldstr      "clicky"
!>     IL_000c: ldstr      "message"
        IL_0011: newobj     instance void [Microsoft.JScript]Microsoft.JScript.LateBinding::.ctor(string)
        IL_0016: stloc.3
<!     IL_0017: ldstr      "Show"
!>     IL_0017: ldstr      "clicky"
        IL_001c: newobj     instance void [Microsoft.JScript]Microsoft.JScript.LateBinding::.ctor(string)
        IL_0021: stloc.s    V_4
<!     IL_0023: ldstr      "message"
<!     IL_0028: newobj     instance void [Microsoft.JScript]Microsoft.JScript.LateBinding::.ctor(string)
<!     IL_002d: stloc.s    V_5
<!     IL_002f: ldstr      "OK"
<!     IL_0034: newobj     instance void [Microsoft.JScript]Microsoft.JScript.LateBinding::.ctor(string)
<!     IL_0039: stloc.s    V_6
<!     IL_003b: ldstr      "Error"
<!     IL_0040: newobj     instance void [Microsoft.JScript]Microsoft.JScript.LateBinding::.ctor(string)
<!     IL_0045: stloc.s    V_7
<!     IL_0047: ldstr      "Show"
<!     IL_004c: newobj     instance void [Microsoft.JScript]Microsoft.JScript.LateBinding::.ctor(string)
<!     IL_0051: stloc.s    V_8
<!     IL_0053: ldstr      "clicky"
<!     IL_0058: newobj     instance void [Microsoft.JScript]Microsoft.JScript.LateBinding::.ctor(string)
<!     IL_005d: stloc.s    V_9
<!     IL_005f: ldarg.0
<!     IL_0060: callvirt   instance class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.INeedEngine::GetEngine()
<!     IL_0065: call       instance class [Microsoft.JScript]Microsoft.JScript.ScriptObject [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine::ScriptObjectStackTop()
<!     IL_006a: castclass [Microsoft.JScript]Microsoft.JScript.IActivationObject
<!     IL_006f: ldstr      "Button"
<!     IL_0074: ldc.i4.1
<!     IL_0075: callvirt   instance object [Microsoft.JScript]Microsoft.JScript.IActivationObject::GetMemberValue(string,
<!                                                                                                                 int32)
<!     IL_007a: dup
<!     IL_007b: call       bool [Microsoft.JScript]Microsoft.JScript.Binding::IsMissing(object)
<!     IL_0080: brfalse    IL_0090
<!
<!     IL_0085: pop
<!     IL_0086: newobj     instance void [System.Windows.Forms]System.Windows.Forms.Button::.ctor()
<!     IL_008b: br         IL_00b8
<!
<!     IL_0090: ldarg.0
<!     IL_0091: callvirt   instance class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.INeedEngine::GetEngine()
<!     IL_0096: call       instance class [Microsoft.JScript]Microsoft.JScript.ScriptObject [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine::ScriptObjectStackTop()
<!     IL_009b: castclass [Microsoft.JScript]Microsoft.JScript.IActivationObject
<!     IL_00a0: callvirt   instance object [Microsoft.JScript]Microsoft.JScript.IActivationObject::GetDefaultThisObject()
<!     IL_00a5: ldc.i4.0
<!     IL_00a6: newarr     [mscorlib]System.Object
<!     IL_00ab: ldc.i4.1
<!     IL_00ac: ldc.i4.0
<!     IL_00ad: ldarg.0
<!     IL_00ae: callvirt   instance class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.INeedEngine::GetEngine()
<!     IL_00b3: call       object [Microsoft.JScript]Microsoft.JScript.LateBinding::CallValue2(object,
<!                                                                                              object,
<!                                                                                              object[],
<!                                                                                              bool,
<!                                                                                              bool,
<!                                                                                              class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine)
<!     IL_00b8: castclass [System.Windows.Forms]System.Windows.Forms.Button
<!     IL_00bd: stloc.0
<!     IL_00be: ldloc.0
<!     IL_00bf: ldstr      "click"
<!     IL_00c4: callvirt   instance void [System.Windows.Forms]System.Windows.Forms.Control::set_Text(string)
<!     IL_00c9: ldarg.0
<!     IL_00ca: call       instance class [System.Windows.Forms]System.Windows.Forms.Control/ControlCollection [System.Windows.Forms]System.Windows.Forms.Control::get_Controls()
<!     IL_00cf: ldloc.0
<!     IL_00d0: callvirt   instance void [System.Windows.Forms]System.Windows.Forms.Control/ControlCollection::Add(class [System.Windows.Forms]System.Windows.Forms.Control)
!>     IL_0023: newobj     instance void [System.Windows.Forms]System.Windows.Forms.Button::.ctor()
!>     IL_0028: stloc.0
!>     IL_0029: ldloc.0
!>     IL_002a: ldstr      "click"
!>     IL_002f: callvirt   instance void [System.Windows.Forms]System.Windows.Forms.Control::set_Text(string)
!>     IL_0034: ldarg.0
!>     IL_0035: call       instance class [System.Windows.Forms]System.Windows.Forms.Control/ControlCollection [System.Windows.Forms]System.Windows.Forms.Control::get_Controls()
!>     IL_003a: ldloc.0
!>     IL_003b: callvirt   instance void [System.Windows.Forms]System.Windows.Forms.Control/ControlCollection::Add(class [System.Windows.Forms]System.Windows.Forms.Control)
        .try
        {
<!       IL_00d5: ldloc.0
!>       IL_0040: ldloc.0
<!       IL_00d6: ldloc.3
<!       IL_00d7: dup
<!       IL_00d8: ldarg.0
<!       IL_00d9: stfld      object [Microsoft.JScript]Microsoft.JScript.LateBinding::obj
<!       IL_00de: call       instance object [Microsoft.JScript]Microsoft.JScript.LateBinding::GetNonMissingValue()
<!       IL_00e3: castclass [mscorlib]System.EventHandler
<!       IL_00e8: call       instance void [System.Windows.Forms]System.Windows.Forms.Control::add_Click(class [mscorlib]System.EventHandler)
<!       IL_00ed: leave      IL_02d5
!>       IL_0041: ldarg.0
!>       IL_0042: dup
!>       IL_0043: ldvirtftn instance void EventTestForm::clicky(object,
!>                                                                class [mscorlib]System.EventArgs)
!>       IL_0049: newobj     instance void [mscorlib]System.EventHandler::.ctor(object,
!>                                                                               native int)
!>       IL_004e: call       instance void [System.Windows.Forms]System.Windows.Forms.Control::add_Click(class [mscorlib]System.EventHandler)
!>       IL_0053: leave      IL_00b8

        } // end .try
        catch [mscorlib]System.Exception
        {
<!       IL_00f2: ldarg.0
<!       IL_00f3: callvirt   instance class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.INeedEngine::GetEngine()
<!       IL_00f8: call       object [Microsoft.JScript]Microsoft.JScript.Try::JScriptExceptionValue(object,
<!                                                                                                   class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine)
<!       IL_00fd: stloc.1
<!       IL_00fe: ldarg.0
<!       IL_00ff: callvirt   instance class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.INeedEngine::GetEngine()
<!       IL_0104: call       instance class [Microsoft.JScript]Microsoft.JScript.ScriptObject [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine::ScriptObjectStackTop()
<!       IL_0109: castclass [Microsoft.JScript]Microsoft.JScript.IActivationObject
<!       IL_010e: ldstr      "MessageBox"
<!       IL_0113: ldc.i4.2
<!       IL_0114: callvirt   instance object [Microsoft.JScript]Microsoft.JScript.IActivationObject::GetMemberValue(string,
<!                                                                                                                   int32)
<!       IL_0119: dup
<!       IL_011a: call       bool [Microsoft.JScript]Microsoft.JScript.Binding::IsMissing(object)
<!       IL_011f: brfalse    IL_012f
<!
<!       IL_0124: pop
<!       IL_0125: ldtoken    [System.Windows.Forms]System.Windows.Forms.MessageBox
<!       IL_012a: call       class [mscorlib]System.Type [mscorlib]System.Type::GetTypeFromHandle(valuetype [mscorlib]System.RuntimeTypeHandle)
<!       IL_012f: stloc.s    V_10
<!       IL_0131: ldloc.s    V_10
<!       IL_0133: isinst     [System.Windows.Forms]System.Windows.Forms.Control
<!       IL_0138: dup
<!       IL_0139: stloc.s    V_11
<!       IL_013b: brfalse    IL_014c
<!
<!       IL_0140: ldloc.s    V_11
<!       IL_0142: call       instance void [System.Windows.Forms]System.Windows.Forms.Control::Show()
<!       IL_0147: br         IL_0235
<!
<!       IL_014c: ldloc.s    V_10
<!       IL_014e: stloc.s    V_12
<!       IL_0150: ldloc.s    V_4
<!       IL_0152: dup
<!       IL_0153: ldloc.s    V_12
<!       IL_0155: ldarg.0
<!       IL_0156: callvirt   instance class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.INeedEngine::GetEngine()
<!       IL_015b: call       object [Microsoft.JScript]Microsoft.JScript.Convert::ToObject(object,
<!                                                                                          class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine)
<!       IL_0160: stfld      object [Microsoft.JScript]Microsoft.JScript.LateBinding::obj
<!       IL_0165: ldc.i4.4
<!       IL_0166: newarr     [mscorlib]System.Object
<!       IL_016b: dup
<!       IL_016c: ldc.i4.0
<!       IL_016d: ldloc.s    V_5
<!       IL_016f: dup
<!       IL_0170: ldloc.1
<!       IL_0171: ldarg.0
<!       IL_0172: callvirt   instance class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.INeedEngine::GetEngine()
<!       IL_0177: call       object [Microsoft.JScript]Microsoft.JScript.Convert::ToObject(object,
<!                                                                                          class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine)
<!       IL_017c: stfld      object [Microsoft.JScript]Microsoft.JScript.LateBinding::obj
<!       IL_0181: call       instance object [Microsoft.JScript]Microsoft.JScript.LateBinding::GetNonMissingValue()
<!       IL_0186: stelem.ref
<!       IL_0187: dup
<!       IL_0188: ldc.i4.1
<!       IL_0189: ldstr      "Error!"
<!       IL_018e: stelem.ref
<!       IL_018f: dup
<!       IL_0190: ldc.i4.2
<!       IL_0191: ldloc.s    V_6
<!       IL_0193: dup
<!       IL_0194: ldarg.0
<!       IL_0195: callvirt   instance class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.INeedEngine::GetEngine()
<!       IL_019a: call       instance class [Microsoft.JScript]Microsoft.JScript.ScriptObject [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine::ScriptObjectStackTop()
<!       IL_019f: castclass [Microsoft.JScript]Microsoft.JScript.IActivationObject
<!       IL_01a4: ldstr      "MessageBoxButtons"
<!       IL_01a9: ldc.i4.2
<!       IL_01aa: callvirt   instance object [Microsoft.JScript]Microsoft.JScript.IActivationObject::GetMemberValue(string,
<!                                                                                                                   int32)
<!       IL_01af: dup
<!       IL_01b0: call       bool [Microsoft.JScript]Microsoft.JScript.Binding::IsMissing(object)
<!       IL_01b5: brfalse    IL_01c5
<!
<!       IL_01ba: pop
<!       IL_01bb: ldtoken    [System.Windows.Forms]System.Windows.Forms.MessageBoxButtons
<!       IL_01c0: call       class [mscorlib]System.Type [mscorlib]System.Type::GetTypeFromHandle(valuetype [mscorlib]System.RuntimeTypeHandle)
<!       IL_01c5: ldarg.0
<!       IL_01c6: callvirt   instance class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.INeedEngine::GetEngine()
<!       IL_01cb: call       object [Microsoft.JScript]Microsoft.JScript.Convert::ToObject(object,
<!                                                                                          class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine)
<!       IL_01d0: stfld      object [Microsoft.JScript]Microsoft.JScript.LateBinding::obj
<!       IL_01d5: call       instance object [Microsoft.JScript]Microsoft.JScript.LateBinding::GetNonMissingValue()
<!       IL_01da: stelem.ref
<!       IL_01db: dup
<!       IL_01dc: ldc.i4.3
<!       IL_01dd: ldloc.s    V_7
<!       IL_01df: dup
<!       IL_01e0: ldarg.0
<!       IL_01e1: callvirt   instance class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.INeedEngine::GetEngine()
<!       IL_01e6: call       instance class [Microsoft.JScript]Microsoft.JScript.ScriptObject [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine::ScriptObjectStackTop()
<!       IL_01eb: castclass [Microsoft.JScript]Microsoft.JScript.IActivationObject
<!       IL_01f0: ldstr      "MessageBoxIcon"
<!       IL_01f5: ldc.i4.2
<!       IL_01f6: callvirt   instance object [Microsoft.JScript]Microsoft.JScript.IActivationObject::GetMemberValue(string,
<!                                                                                                                   int32)
<!       IL_01fb: dup
<!       IL_01fc: call       bool [Microsoft.JScript]Microsoft.JScript.Binding::IsMissing(object)
<!       IL_0201: brfalse    IL_0211
<!
<!       IL_0206: pop
<!       IL_0207: ldtoken    [System.Windows.Forms]System.Windows.Forms.MessageBoxIcon
<!       IL_020c: call       class [mscorlib]System.Type [mscorlib]System.Type::GetTypeFromHandle(valuetype [mscorlib]System.RuntimeTypeHandle)
<!       IL_0211: ldarg.0
<!       IL_0212: callvirt   instance class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.INeedEngine::GetEngine()
<!       IL_0217: call       object [Microsoft.JScript]Microsoft.JScript.Convert::ToObject(object,
<!                                                                                          class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine)
<!       IL_021c: stfld      object [Microsoft.JScript]Microsoft.JScript.LateBinding::obj
<!       IL_0221: call       instance object [Microsoft.JScript]Microsoft.JScript.LateBinding::GetNonMissingValue()
<!       IL_0226: stelem.ref
<!       IL_0227: ldc.i4.0
<!       IL_0228: ldc.i4.0
<!       IL_0229: ldarg.0
<!       IL_022a: callvirt   instance class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.INeedEngine::GetEngine()
<!       IL_022f: call       instance object [Microsoft.JScript]Microsoft.JScript.LateBinding::Call(object[],
<!                                                                                                   bool,
<!                                                                                                   bool,
<!                                                                                                   class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine)
<!       IL_0234: pop
<!       IL_0235: ldarg.0
<!       IL_0236: callvirt   instance class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.INeedEngine::GetEngine()
<!       IL_023b: call       instance class [Microsoft.JScript]Microsoft.JScript.ScriptObject [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine::ScriptObjectStackTop()
<!       IL_0240: castclass [Microsoft.JScript]Microsoft.JScript.IActivationObject
<!       IL_0245: ldstr      "MessageBox"
<!       IL_024a: ldc.i4.2
<!       IL_024b: callvirt   instance object [Microsoft.JScript]Microsoft.JScript.IActivationObject::GetMemberValue(string,
<!                                                                                                                   int32)
<!       IL_0250: dup
<!       IL_0251: call       bool [Microsoft.JScript]Microsoft.JScript.Binding::IsMissing(object)
<!       IL_0256: brfalse    IL_0266
<!
<!       IL_025b: pop
<!       IL_025c: ldtoken    [System.Windows.Forms]System.Windows.Forms.MessageBox
<!       IL_0261: call       class [mscorlib]System.Type [mscorlib]System.Type::GetTypeFromHandle(valuetype [mscorlib]System.RuntimeTypeHandle)
<!       IL_0266: stloc.s    V_13
<!       IL_0268: ldloc.s    V_13
<!       IL_026a: isinst     [System.Windows.Forms]System.Windows.Forms.Control
<!       IL_026f: dup
<!       IL_0270: stloc.s    V_14
<!       IL_0272: brfalse    IL_0283
<!
<!       IL_0277: ldloc.s    V_14
<!       IL_0279: call       instance void [System.Windows.Forms]System.Windows.Forms.Control::Show()
<!       IL_027e: br         IL_02d0
<!
<!       IL_0283: ldloc.s    V_13
<!       IL_0285: stloc.s    V_15
<!       IL_0287: ldloc.s    V_8
<!       IL_0289: dup
<!       IL_028a: ldloc.s    V_15
<!       IL_028c: ldarg.0
<!       IL_028d: callvirt   instance class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.INeedEngine::GetEngine()
<!       IL_0292: call       object [Microsoft.JScript]Microsoft.JScript.Convert::ToObject(object,
<!                                                                                          class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine)
<!       IL_0297: stfld      object [Microsoft.JScript]Microsoft.JScript.LateBinding::obj
<!       IL_029c: ldc.i4.1
<!       IL_029d: newarr     [mscorlib]System.Object
<!       IL_02a2: dup
<!       IL_02a3: ldc.i4.0
<!       IL_02a4: ldstr      "clicky is a "
<!       IL_02a9: ldloc.s    V_9
<!       IL_02ab: dup
<!       IL_02ac: ldarg.0
<!       IL_02ad: stfld      object [Microsoft.JScript]Microsoft.JScript.LateBinding::obj
<!       IL_02b2: call       instance object [Microsoft.JScript]Microsoft.JScript.LateBinding::GetNonMissingValue()
<!       IL_02b7: call       string [Microsoft.JScript]Microsoft.JScript.Typeof::JScriptTypeof(object)
<!       IL_02bc: call       string [mscorlib]System.String::Concat(string,
<!                                                                   string)
<!       IL_02c1: stelem.ref
<!       IL_02c2: ldc.i4.0
<!       IL_02c3: ldc.i4.0
<!       IL_02c4: ldarg.0
<!       IL_02c5: callvirt   instance class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.INeedEngine::GetEngine()
<!       IL_02ca: call       instance object [Microsoft.JScript]Microsoft.JScript.LateBinding::Call(object[],
<!                                                                                                   bool,
<!                                                                                                   bool,
<!                                                                                                   class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine)
<!       IL_02cf: pop
<!       IL_02d0: leave      IL_02d5
!>       IL_0058: ldarg.0
!>       IL_0059: callvirt   instance class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.INeedEngine::GetEngine()
!>       IL_005e: call       object [Microsoft.JScript]Microsoft.JScript.Try::JScriptExceptionValue(object,
->                                                                                                   class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine)
!>       IL_0063: stloc.1
!>       IL_0064: ldloc.3
!>       IL_0065: dup
!>       IL_0066: ldloc.1
->       IL_0067: ldarg.0
->       IL_0068: callvirt   instance class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.INeedEngine::GetEngine()
->       IL_006d: call       object [Microsoft.JScript]Microsoft.JScript.Convert::ToObject(object,
->                                                                                          class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine)
->       IL_0072: stfld      object [Microsoft.JScript]Microsoft.JScript.LateBinding::obj
!>       IL_0077: call       instance object [Microsoft.JScript]Microsoft.JScript.LateBinding::GetNonMissingValue()
!>       IL_007c: ldc.i4.1
!>       IL_007d: call       string [Microsoft.JScript]Microsoft.JScript.Convert::ToString(object,
!>                                                                                          bool)
!>       IL_0082: ldstr      "Error!"
!>       IL_0087: ldc.i4.0
!>       IL_0088: ldc.i4.s   16
!>       IL_008a: call       valuetype [System.Windows.Forms]System.Windows.Forms.DialogResult [System.Windows.Forms]System.Windows.Forms.MessageBox::Show(string,
!>                                                                                                                                                          string,
!>                                                                                                                                                          valuetype [System.Windows.Forms]System.Windows.Forms.MessageBoxButtons,
!>                                                                                                                                                          valuetype [System.Windows.Forms]System.Windows.Forms.MessageBoxIcon)
!>       IL_008f: pop
!>       IL_0090: ldstr      "clicky is a "
!>       IL_0095: ldloc.s    V_4
!>       IL_0097: dup
!>       IL_0098: ldarg.0
!>       IL_0099: stfld      object [Microsoft.JScript]Microsoft.JScript.LateBinding::obj
!>       IL_009e: call       instance object [Microsoft.JScript]Microsoft.JScript.LateBinding::GetNonMissingValue()
!>       IL_00a3: call       string [Microsoft.JScript]Microsoft.JScript.Typeof::JScriptTypeof(object)
!>       IL_00a8: call       string [mscorlib]System.String::Concat(string,
!>                                                                   string)
!>       IL_00ad: call       valuetype [System.Windows.Forms]System.Windows.Forms.DialogResult [System.Windows.Forms]System.Windows.Forms.MessageBox::Show(string)
!>       IL_00b2: pop
!>       IL_00b3: leave      IL_00b8

        } // end handler
<!     IL_02d5: ret
!>     IL_00b8: ret
      } // end of method EventTestForm::.ctor

      .method private specialname rtspecialname static
              void .cctor() cil managed
      {
        // Code size       1 (0x1)
        .maxstack 0
        IL_0000: ret
      } // end of method EventTestForm::.cctor

      .method private instance void '.init'() cil managed
      {
        // Code size       1 (0x1)
        .maxstack 0
        IL_0000: ret
      } // end of method EventTestForm::'.init'

<!   .method public static string 'EventTestForm source'() cil managed
<!   {
<!     // Code size       6 (0x6)
<!     .maxstack 1
<!     IL_0000: ldstr      "function EventTestForm()\r\n \t{\r\n\t\tvar button : But"
<!     + "ton = new Button;\r\n\r\n\t\tbutton.Text = \"click\";\r\n\r\n\t\tControls.Add(button)"
<!     + ";\r\n\r\n\t\ttry\r\n\t\t{\r\n\t\t\tbutton.add_Click(this.clicky);\r\n\t\t}\r\n\t\tcatch(er)\r\n\t"
<!     + "\t{\r\n\t\t\tMessageBox.Show(er.message,\"Error!\",MessageBoxButtons.OK,Message"
<!     + "BoxIcon.Error);\r\n\t\t\tMessageBox.Show(\"clicky is a \" + typeof this.clicky"
<!     + ");\r\n\t\t}\r\n\t}"
<!     IL_0005: ret
<!   } // end of method EventTestForm::'EventTestForm source'
<!
      .method public hidebysig newslot virtual
              instance void clicky(object obj,
                                    class [mscorlib]System.EventArgs evt) cil managed
      {
<!     // Code size       171 (0xab)
<-     .maxstack 11
<!     .locals init (class [Microsoft.JScript]Microsoft.JScript.LateBinding V_0,
<!              class [Microsoft.JScript]Microsoft.JScript.LateBinding V_1,
<!              object V_2,
<!              class [System.Windows.Forms]System.Windows.Forms.Control V_3,
<!              object V_4)
<!     IL_0000: ldstr      "Show"
!>     // Code size       46 (0x2e)
!>     .maxstack 4
->     .locals init (class [Microsoft.JScript]Microsoft.JScript.LateBinding V_0)
!>     IL_0000: ldstr      "clicky"
        IL_0005: newobj     instance void [Microsoft.JScript]Microsoft.JScript.LateBinding::.ctor(string)
        IL_000a: stloc.0
<!     IL_000b: ldstr      "clicky"
<!     IL_0010: newobj     instance void [Microsoft.JScript]Microsoft.JScript.LateBinding::.ctor(string)
<!     IL_0015: stloc.1
<!     IL_0016: ldarg.0
<!     IL_0017: callvirt   instance class [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine [Microsoft.JScript]Microsoft.JScript.INeedEngine::GetEngine()
<!     IL_001c: call       instance class [Microsoft.JScript]Microsoft.JScript.ScriptObject [Microsoft.JScript]Microsoft.JScript.Vsa.VsaEngine::ScriptObjectStackTop()
<!     IL_0021: castclass [Microsoft.JScript]Microsoft.JScript.IActivationObject
<!     IL_0026: ldstr      "MessageBox"
<!     IL_002b: ldc.i4.1
<!     IL_002c: callvirt   instance object [Microsoft.JScript]Microsoft.JScript.IActivationObject::GetMemberValue(string,
<!                                                                                                                 int32)
<-     IL_0031: dup
<!     IL_0032: call       bool [Microsoft.JScript]Microsoft.JScript.Binding::IsMissing(object)
<!     IL_0037: brfalse    IL_0047
<!
<!     IL_003c: pop
<!     IL_003d: ldtoken    [System.Windows.Forms]System.Windows.Forms.MessageBox
<!     IL_0042: call       class [mscorlib]System.Type [mscorlib]System.Type::GetTypeFromHandle(valuetype [mscorlib]System.RuntimeTypeHandle)
<!     IL_0047: stloc.2
<!     IL_0048: ldloc.2
<!     IL_0049: isinst     [System.Windows.Forms]System.Windows.Forms.Control
<!     IL_004e: dup
<!     IL_004f: stloc.3
<!     IL_0050: brfalse    IL_0060
<!
<!     IL_0055: ldloc.3
<!     IL_0056: call       instance void [System.Windows.Forms]System.Windows.Forms.Control::Show()
<!     IL_005b: br         IL_00aa
<!
<!     IL_0060: ldloc.2
<!