lib/as3/notes.txt

   1 -----------------------------------------------------------------------
   2
   3     var x = a
   4     [ExcludeClass(...)]
   5
   6 [x=a at [ExcludeClass(...)] or x=a, then embed command?]
   7
   8 -----------------------------------------------------------------------
   9
  10     if(1==2)
  11         return
  12     i++
  13
  14 [return i++ or just return?]
  15
  16 -----------------------------------------------------------------------
  17
  18     x = 3
  19     /abc/
  20     y++
  21
  22 [x=3;regexp abc;y++ or x divided by abc divided by y++?]
  23
  24 -----------------------------------------------------------------------
  25
  26     x = 5
  27     -obj
  28
  29 [x=5, evaluate "minus obj" or x=5-obj?]
  30
  31 -----------------------------------------------------------------------
  32
  33     x = y as X.z
  34
  35 [coerce y to static field z of X, or coerce y to X, then evaluate member z?]
  36
  37 -----------------------------------------------------------------------
  38     if(1==2)
  39         return
  40     { myloop: i++;}
  41
  42 [return object:{myloop:i++} or execute code block with myloop label?]
  43
  44
  45 -----------------------------------------------------------------------
  46
  47     for(i in a in a; ...)
  48
  49 [only after encountering the first ; it becomes clear that this is in
  50  fact *not* a for-in loop]
  51
  52 -----------------------------------------------------------------------
  53
  54     var x =
  55     namespace1 ++ namespace2
  56     function test()
  57     {
  58     }
  59
  60 [x = namespace1, increment namespace2? or is test in namespace2?]
  61
  62 -----------------------------------------------------------------------
  63
  64
  65     x = (a[Math.random(100)] += 10)
  66
  67 code needed for this:
  68
  69     [calculate Math.random(100), gives us two stack values]
  70     dup2 [a.k.a. setlocal tmp, dup , getlocal tmp, swap, getlocal tmp]
  71     getproperty (consumes two stack values)
  72     [code for adding 10]
  73     setlocal tmp (we don't have *any* kind of useful stack exchange operations, so no way around a local register)
  74     setproperty (consumes two stack values again)
  75     getlocal tmp
  76     kill tmp (so the verifier is happy)
  77     setlocal x (finally!)
  78
  79 -----------------------------------------------------------------------
  80
  81 VerifyError: Error #1030: Stack depth is unbalanced. 0 != 1.
  82
  83 0 : local position
  84 1 : position I'm jumping to
  85
  86 -----------------------------------------------------------------------
  87
  88 Verifier is buggy:
  89
  90 verify test.package::Main()
  91                         stack:
  92                         scope: [global Object$ flash.events::EventDispatcher$ flash.display::DisplayObject$ flash.display::InteractiveObject$ flash.display::DisplayObjectContainer$ flash.display::Sprite$ flash.display::MovieClip$ test.package::Main$]
  93                          locals: test.package::Main
  94   0:getlocal0
  95                         stack: test.package::Main
  96                         scope: [global Object$ flash.events::EventDispatcher$ flash.display::DisplayObject$ flash.display::InteractiveObject$ flash.display::DisplayObjectContainer$ flash.display::Sprite$ flash.display::MovieClip$ test.package::Main$]
  97                          locals: test.package::Main
  98   1:pushscope
  99                         stack:
 100                         scope: [global Object$ flash.events::EventDispatcher$ flash.display::DisplayObject$ flash.display::InteractiveObject$ flash.display::DisplayObjectContainer$ flash.display::Sprite$ flash.display::MovieClip$ test.package::Main$] test.package::Main
 101                          locals: test.package::Main
 102   2:jump 7
 103 B0:
 104                         stack:
 105                         scope: [global Object$ flash.events::EventDispatcher$ flash.display::DisplayObject$ flash.display::InteractiveObject$ flash.display::DisplayObjectContainer$ flash.display::Sprite$ flash.display::MovieClip$ test.package::Main$] test.package::Main
 106                          locals: test.package::Main?
 107   6:label
 108 B1:
 109                         stack:
 110                         scope: [global Object$ flash.events::EventDispatcher$ flash.display::DisplayObject$ flash.display::InteractiveObject$ flash.display::DisplayObjectContainer$ flash.display::Sprite$ flash.display::MovieClip$ test.package::Main$] test.package::Main?
 111                          locals: test.package::Main?
 112   7:label
 113                         stack:
 114                         scope: [global Object$ flash.events::EventDispatcher$ flash.display::DisplayObject$ flash.display::InteractiveObject$ flash.display::DisplayObjectContainer$ flash.display::Sprite$ flash.display::MovieClip$ test.package::Main$] test.package::Main?
 115                          locals: test.package::Main?
 116   8:pushfalse
 117                         stack: Boolean
 118                         scope: [global Object$ flash.events::EventDispatcher$ flash.display::DisplayObject$ flash.display::InteractiveObject$ flash.display::DisplayObjectContainer$ flash.display::Sprite$ flash.display::MovieClip$ test.package::Main$] test.package::Main?
 119                          locals: test.package::Main?
 120   9:iftrue 6
 121 VerifyError: Error #1068: test.package.Main and test.package.Main cannot be reconciled.
 122
 123         at test.package::Main()
 124
 125
 126 static void xx_scopetest()
 127 {
 128     /* findpropstrict doesn't just return a scope object- it
 129        also makes it "active" somehow. Push local_0 on the
 130        scope stack and read it back with findpropstrict, it'll
 131        contain properties like "trace". Trying to find the same
 132        property on a "vanilla" local_0 yields only a "undefined" */
 133     //c = abc_findpropstrict(c, "[package]::trace");
 134
 135     /*c = abc_getlocal_0(c);
 136     c = abc_findpropstrict(c, "[package]::trace");
 137     c = abc_coerce_a(c);
 138     c = abc_setlocal_1(c);
 139
 140     c = abc_pushbyte(c, 0);
 141     c = abc_setlocal_2(c);
 142
 143     code_t*xx = c = abc_label(c);
 144     c = abc_findpropstrict(c, "[package]::trace");
 145     c = abc_pushstring(c, "prop:");
 146     c = abc_hasnext2(c, 1, 2);
 147     c = abc_dup(c);
 148     c = abc_setlocal_3(c);
 149     c = abc_callpropvoid(c, "[package]::trace", 2);
 150     c = abc_getlocal_3(c);
 151     c = abc_kill(c, 3);
 152     c = abc_iftrue(c,xx);*/
 153 }