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     push a
  70     calculate Math.random(100), push
  71     dup2 [a.k.a. setlocal tmp, dup , getlocal tmp, swap, getlocal tmp]
  72     getproperty (consumes two stack values)
  73     [code for adding 10]
  74     setlocal tmp (we don't have *any* kind of useful stack exchange operations, so no way around a local register)
  75     setproperty (consumes two stack values again)
  76     getlocal tmp
  77     kill tmp (so the verifier is happy)
  78     setlocal x (finally!)
  79
  80 -----------------------------------------------------------------------
  81
  82 VerifyError: Error #1030: Stack depth is unbalanced. 0 != 1.
  83
  84 0 : local position
  85 1 : position I'm jumping to
  86
  87 -----------------------------------------------------------------------
  88
  89 Verifier is buggy:
  90
  91 verify test.package::Main()
  92                         stack:
  93                         scope: [global Object$ flash.events::EventDispatcher$ flash.display::DisplayObject$ flash.display::InteractiveObject$ flash.display::DisplayObjectContainer$ flash.display::Sprite$ flash.display::MovieClip$ test.package::Main$]
  94                          locals: test.package::Main
  95   0:getlocal0
  96                         stack: test.package::Main
  97                         scope: [global Object$ flash.events::EventDispatcher$ flash.display::DisplayObject$ flash.display::InteractiveObject$ flash.display::DisplayObjectContainer$ flash.display::Sprite$ flash.display::MovieClip$ test.package::Main$]
  98                          locals: test.package::Main
  99   1:pushscope
 100                         stack:
 101                         scope: [global Object$ flash.events::EventDispatcher$ flash.display::DisplayObject$ flash.display::InteractiveObject$ flash.display::DisplayObjectContainer$ flash.display::Sprite$ flash.display::MovieClip$ test.package::Main$] test.package::Main
 102                          locals: test.package::Main
 103   2:jump 7
 104 B0:
 105                         stack:
 106                         scope: [global Object$ flash.events::EventDispatcher$ flash.display::DisplayObject$ flash.display::InteractiveObject$ flash.display::DisplayObjectContainer$ flash.display::Sprite$ flash.display::MovieClip$ test.package::Main$] test.package::Main
 107                          locals: test.package::Main?
 108   6:label
 109 B1:
 110                         stack:
 111                         scope: [global Object$ flash.events::EventDispatcher$ flash.display::DisplayObject$ flash.display::InteractiveObject$ flash.display::DisplayObjectContainer$ flash.display::Sprite$ flash.display::MovieClip$ test.package::Main$] test.package::Main?
 112                          locals: test.package::Main?
 113   7:label
 114                         stack:
 115                         scope: [global Object$ flash.events::EventDispatcher$ flash.display::DisplayObject$ flash.display::InteractiveObject$ flash.display::DisplayObjectContainer$ flash.display::Sprite$ flash.display::MovieClip$ test.package::Main$] test.package::Main?
 116                          locals: test.package::Main?
 117   8:pushfalse
 118                         stack: Boolean
 119                         scope: [global Object$ flash.events::EventDispatcher$ flash.display::DisplayObject$ flash.display::InteractiveObject$ flash.display::DisplayObjectContainer$ flash.display::Sprite$ flash.display::MovieClip$ test.package::Main$] test.package::Main?
 120                          locals: test.package::Main?
 121   9:iftrue 6
 122 VerifyError: Error #1068: test.package.Main and test.package.Main cannot be reconciled.
 123
 124         at test.package::Main()
 125
 126
 127 static void xx_scopetest()
 128 {
 129     /* findpropstrict doesn't just return a scope object- it
 130        also makes it "active" somehow. Push local_0 on the
 131        scope stack and read it back with findpropstrict, it'll
 132        contain properties like "trace". Trying to find the same
 133        property on a "vanilla" local_0 yields only a "undefined" */
 134     //c = abc_findpropstrict(c, "[package]::trace");
 135
 136     /*c = abc_getlocal_0(c);
 137     c = abc_findpropstrict(c, "[package]::trace");
 138     c = abc_coerce_a(c);
 139     c = abc_setlocal_1(c);
 140
 141     c = abc_pushbyte(c, 0);
 142     c = abc_setlocal_2(c);
 143
 144     code_t*xx = c = abc_label(c);
 145     c = abc_findpropstrict(c, "[package]::trace");
 146     c = abc_pushstring(c, "prop:");
 147     c = abc_hasnext2(c, 1, 2);
 148     c = abc_dup(c);
 149     c = abc_setlocal_3(c);
 150     c = abc_callpropvoid(c, "[package]::trace", 2);
 151     c = abc_getlocal_3(c);
 152     c = abc_kill(c, 3);
 153     c = abc_iftrue(c,xx);*/
 154 }