[Laszlo-dev] For Review: Change 20080222-dda-o Summary: Add support for new dependency mechanism in script compiler

[Donald Anderson]

Change 20080222-dda-o by dda at lester.local on 2008-02-22 21:31:39 EST
     in /Users/dda/laszlo/src/svn/openlaszlo/trunk-dep
     for http://svn.openlaszlo.org/openlaszlo/trunk

Summary: Add support for new dependency mechanism in script compiler

New Features:

Bugs Fixed: LPP-5335 (partial)

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

Documentation:

Release Notes:

Details:
     Introduces a new function Compiler.dependenciesForExpression()  
taking
     a source expression e.g. "a.b.c + this.something.Fcn(1)" and
     producing a source expression representing the dependency, e.g.
       [a.b, "c"].concat(this.something.hasOwnProperty("$lsc 
$Fcn_dependencies") ? (this.something cast Object).$lsc 
$Fcn_dependencies(this, this.something, 1) : [])

     This change does not functionally change *anything*, but it  
provides
     an API needed to switch over to having the tag compiler generate  
the
     dependency functions.

     The significant changes are in ReferenceCollector, which keeps two
     implementations (old and new) for the moment.  It doesn't make  
sense
     to refactor them into a common codebase since the old  
implementation
     will go away after new dependencies are fully integrated.  The  
old implementation
     internal methods can be found in ReferenceCollector named as  
*_using_subfunction
     in reference to the original naming convention fcn() ->  
fcn.dependencies() .

     The new implementation uses naming fcn() -> $lsc 
$fcn_dependencies() as
     indicated in the example above.
     The implementation is conscious of the naming convention, since  
there
     may be calls to the dependency functions in the produced output.

     There is also a fix to the ParseTreePrinter so that it knows how  
to print
     'cast'.  This wasn't needed before to print final output from  
JS1, since
     casts were always removed.  Casts are generated in the dependency  
source
     so they will work with SWF9 - without it, the flex compile  
complains
     about references to nonexistant dependency functions.   
Downcasting to
     Object makes the compiler *less* strict and accepting of any  
function name.
     The output from the simple dependency given above has been tested  
to
     compile with flex2 as a proof of concept.

     Also a small improvement to ReferenceGenerator to only create one  
Compiler.Parser object.

     This snippet added to NodeModel.java during testing (but not part  
of this change)
     shows how the new dependency function can be called:

         if (when.equals(WHEN_ALWAYS)) {
             System.out.println("CONSTRAINT: src = " +  
canonicalValue.toString());
             String dep = (new  
org 
.openlaszlo 
.sc.Compiler()).dependenciesForExpression(canonicalValue.toString());
             System.out.println("CONSTRAINT: dep = " + dep);
         }


Tests:
     regression: smokecheck,weather,lzpix (swf8/dhtml), runlzunit

Files:
M      WEB-INF/lps/server/src/org/openlaszlo/sc/ReferenceCollector.java
M      WEB-INF/lps/server/src/org/openlaszlo/sc/Compiler.java
M      WEB-INF/lps/server/src/org/openlaszlo/sc/ParseTreePrinter.java

Changeset: http://svn.openlaszlo.org/openlaszlo/patches/20080222-dda-o.tar



--

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

voice: 617-547-7881
email: dda at ddanderson.com
www: http://www.ddanderson.com