[Laszlo-dev] For Review: Change 20071107-dda-g Summary: Allow type information for vars, even though ignored in SWF7/8 and DHTML.

[Donald Anderson]

Change 20071107-dda-g by dda at freddie.local on 2007-11-07 18:14:27 EST
     in /Users/dda/laszlo/src/svn/openlaszlo/trunk
     for http://svn.openlaszlo.org/openlaszlo/trunk

Summary: Allow type information for vars, even though ignored in  
SWF7/8 and DHTML.

New Features:
     Allow type information accepted in ActionScript 3.0, that is:
       var x:int;
       var y:String = "hello";
       var z:?String = null;   // ? means can set to null (default)
       var z:String! = "bonjour";   // ! means cannot set to null
     Please note that the type information is merely accepted as part  
of the language, and ignored for now.

Bugs Fixed: LPP-5059

Technical Reviewer: ptw
QA Reviewer: philip
Doc Reviewer: (pending)

Documentation:
    Requires documentation if we describe in detail our language (or  
subset).  If we point
    users to the published standards, then we can continue to do that.
    We should note that type information is ignored except for the  
(upcoming) SWF9 runtime.

Release Notes:
     Variables declared using the 'var' statement now allow type  
specifications as
     described by Ecmascript 4 (that is, ActionScript 3.0).

Details:
     No type checking is done by the SWF7/8 and DHTML runtimes (nor  
is planned), any
     type information is thrown away.  However, when SWF9 is  
available, the type information
     will be accepted and passed through to the 3rd party SWF9  
compiler, which will do type
     checking for any variable with type information.  This change  
allows users and developers
     to write code that can be useful with either runtime.  Even if  
they don't use with SWF9,
     this is a useful feature for self documenting usage of variables.

     We currently allow type information on 'var' declarations, also  
method parameters and
     method return values.  I believe only information for 'var'  
declarations can be done
     in .lzx, but the latter two are also accepted (and ignored for  
current runtimes) in .lzs files.

Tests:
     Ran new test test/typevar.lzx for both SWF7/8 and DHTML, to make  
sure syntax is accepted.
     Ran smokecheck.lzx to assure there are no regressions.

Files:
A      test/typevar.lzx
M      WEB-INF/lps/server/sc/src/org/openlaszlo/sc/Parser.jjt
M      WEB-INF/lps/server/sc/src/org/openlaszlo/sc/parser/ 
ASTIdentifier.java

Changeset: http://svn.openlaszlo.org/openlaszlo/patches/20071107-dda- 
g.tar



--

Don Anderson
Java/C/C++, Berkeley DB, systems consultant

Voice:  617-547-7881
Email:  dda at ddanderson.com
WWW:    http://www.ddanderson.com