[Laszlo-dev] For Review: Change 20090415-ptw-w Summary: Improve catch-errors and backtrace efficiency

[André Bargull]

Why do you return the empty string if returnType is "String"? Strings 
can be `null`. And you've missed to include "int" and "uint" (both are 
coerced to 0 in AS3).
I'd say the return values should be (for best cross-runtime compliance):
void -> no return
int, uint, Number -> 0
Boolean -> false
all other -> null

<canvas debug="true">
  <script when="immediate"><![CDATA[
    public class Foo {
      // void must not have return value in AS3
      // public function f_void () :void {return null;}
      // coerced to 0 in AS3
      public function f_int () :int {return null;}
      // coerced to 0 in AS3
      public function f_uint () :uint {return null;}
      // coerced to 0 in AS3
      public function f_Number () :Number {return null;}
      // coerced to false in AS3
      public function f_Boolean () :Boolean {return null;}
      // returns null
      public function f_String () :String {return null;}
      // returns null
      public function f_Object () :Object {return null;}
      // returns null
      public function f_Date () :Date {return null;}
    }
    // make a reference to class so it'll be compiled...
    Foo;
  ]]></script>
</canvas>

On 4/16/2009 1:54 AM, P T Withington wrote:
> Change 20090415-ptw-w by ptw at dueling-banjos.home on 2009-04-15 
> 19:34:51 EDT
>     in /Users/ptw/OpenLaszlo/trunk-3
>     for http://svn.openlaszlo.org/openlaszlo/trunk
>
> Summary: Improve catch-errors and backtrace efficiency
>
> Bugs Fixed: LPP-8008 Optimize catcherrors
>
> Technical Reviewer: a.bargull at intensis.de, hminksy (pending)
> QA Reviewer: dda at ddanderson.com (pending)
>
> Details:
>     LzMessage: Correct stack skip for $reportSourceWarning (which was
>     one too many).
>
>     JavascriptGenerator:  Eliminate the need for the inner closure to
>     catch errors.  Merge catching of errors with the backtrace
>     maintainer.
>
>     - noteCallSite should only emit line numbers for positive line
>       numbers (generated nodes sometimes have -1 as a line number).
>
>     - predecls no longer needed, but need postfix to insert a default
>       return value to keep the flex compiler happy.
>
>     - Only enable catching of errors if variable analysis shows that
>       there are dereferences (calls, or property references) that
>       could err
>
>     - If generating for swf9 and catching errors, insert a 'null'
>       return at the end of the function that matches the return type
>       of the function to mimic as2.
>
>     - Eliminate the inner closure for tryAll, we can just wrap the
>       body directly in a try/catch and eliminate the extra function
>       call overhead.
>
>     VariableAnalyzer: Make it possible to call computeReferences more
>     than once (so we can analyze the body before and after the try
>     wrapper is added).  Also, calculate a new property, dereferenced,
>     that tells if any calls or property references occured.
>
> Tests:
>     Turned on lps.properties:compiler.catcherrors, [all demos, 
> smokecheck] x [dhtml, swf9]
>
> Files:
> M      WEB-INF/lps/lfc/debugger/LzMessage.lzs
> M      WEB-INF/lps/server/src/org/openlaszlo/sc/JavascriptGenerator.java
> M      WEB-INF/lps/server/src/org/openlaszlo/sc/VariableAnalyzer.java
>
>
> Changeset: 
> http://svn.openlaszlo.org/openlaszlo/patches/20090415-ptw-w.tar
>