[Laszlo-dev] For Review: Change 20071128-ptw-S Summary: Don't try to be so cute about using implicit semicolons in

[Donald Anderson]

Some questions before approval:

You're checking for "(" so that
   xx;
   (yy)
is not joined as xx(yy), right?
But don't we have the same problem with
   xx;
   -yy
Since expression statements can be arbitrary expressions.  Looks like
unary plus (xx; +yy) might have the same problem.  Granted these  
would be strange
to encounter in the wild, but I'm wary of the special case -  
especially when
I'm not sure there aren't others.  Or am I missing something?

Nit:
       this.SEMI = ";" + (compress ? SPACE : NEWLINE);
would probably be more readable as
       this.SEMI = ";" + (compress ? "" : NEWLINE);

- Don

On Nov 28, 2007, at 1:49 PM, P T Withington wrote:

> Change 20071128-ptw-S by ptw at dueling-banjos.local on 2007-11-28  
> 13:17:43 EST
>     in /Users/ptw/OpenLaszlo/ringding-2
>     for http://svn.openlaszlo.org/openlaszlo/trunk
>
> Summary: Don't try to be so cute about using implicit semicolons in
>     Javascript compiler
>
> Bugs Fixed:
> LPP-5130 'resources in DHTML fail with "is not a function'" error'
>
> Technical Reviewer: dda at ddanderson.com (pending)
> QA Reviewer: enw (pending)
>
> Details:
>     We used to try to be clever and use newlines in place of
>     semicolons in our 'compressed' code so that the code was a little
>     more human-readable (and debuggable, using the native browser
>     debugger).  But this cuteness was just broken and caused some
>     expressions to not be interpreted as statements (and often to be
>     interpreted as function calls).  Without a huge amount of work, it
>     is difficult to correctly compute where an implicit semicolon can
>     be used.
>
>     Instead, we now always end a statement with a semicolon and only
>     elide them before the close brace of a block (which is easily
>     computable).  And, we output blocks a little more compactly,
>     actually improving the 'compression' of our Javascript output.
>
>     The primary change is to remove the old heuristic that inserted
>     semicolons in between statements in a statement list, and to
>     explicitly append one to each statement.  Put all the block
>     building in one method instead of inlining it all over the place.
>
> Tests:
>     smokecheck, test case in bug, lzmail in DHTML now gets past the
>     reported error
>
> Files:
> M      WEB-INF/lps/server/src/org/openlaszlo/sc/Compiler.java
>
>
> Changeset: http://svn.openlaszlo.org/openlaszlo/patches/20071128- 
> ptw-S.tar


--

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

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