[Laszlo-dev] Previous results of debugger evals

[P T Withington]

Yes, they should be accessible in complex expressions (evaluated in  
the debugger).  And yes, it is probably a simple matter of updating  
compileAndWriteToSWF.  I just think no one ever got around to it.  It  
would be great if you want to do that.

On 2009-09-27, at 08:49, André Bargull wrote:

> So, should it be possible to access these shortcuts anywhere else  
> than while eval'ing an expression and/or should it be possible to  
> use them in complex expressions? At least according to the Lisp  
> reference, it should be possible to use them in complex expressions,  
> but that's currently only possible in swf8 and dhtml. And only in  
> swf8, you can access the values globally, but that doesn't seem to  
> be intended as you said below.
> If Compiler#compileAndWriteToSWF() and Compiler#compileAndWriteToAS3 
> () are changed to include `with (Debug.environment) { ... }`, it  
> should be possible to use the shortcuts in complex expressions and  
> avoid polluting the global namespace. These changes seem to be quite  
> easy or did I miss anything?
>
>
> On 9/27/2009 1:46 PM, P T Withington wrote:
>> These are shortcuts that old Lisp hackers know by heart (http://bit.ly/2Ll3qS 
>> ), although they have been renamed to be legal Javascript symbols.   
>> This is why we have not felt any need to document them.  :)
>> They are supposed to work in all runtimes.  In an attempt to reduce  
>> global namespace pollution, I moved them out of the global  
>> namespace into `Debug.environment` (which is where they more  
>> properly belong -- the Debugger should not be storing its state in  
>> the application's namespace), as is stated in your first  
>> reference.  See the note at  line 91 of swf9/LzDebug.as.  What  
>> really needs to happen is for the swf9 debug evaluator to wrap  
>> `with (Debug.environment) { ... }` around the expressions it  
>> compiles, just as dhtml/LzDebug.js does in `doEval`.  I think this  
>> has to happen in the compiler, not the debugger, because of the  
>> other code the compiler wraps around evaluations to heuristicate  
>> whether it is an expression or statement and to report errors.
>> On 2009-09-27, at 07:06, André Bargull wrote:
>>> The last three results of debugger evals are stored in '_', '__'  
>>> and '___' to provide a fast way to access these values again.  
>>> Currently, swf8 stores the values in the global object, whereas  
>>> AS3 runtimes store the values in the global object "global". This  
>>> means in swf8 you could write 'Debug.write("last result was %#w",  
>>> _)', but this is currently not possible in swf9/swf10. My  
>>> question: Should this be considered as a bug? I don't think there  
>>> is any official documentation for these short-hands [1], so maybe  
>>> it was only intended that '_' as a single expression should work?!
>>>
>>> PS: '_' as a single expression works in swf9/swf10, because that's  
>>> a "simple expression" and therefore handled by "evalSimpleExpr"  
>>> which calls "globalValue" and "globalValue" looks up values in the  
>>> global object "global".
>>>
>>> [1] Google only found these two results:
>>> - http://www.openlaszlo.org/pipermail/laszlo-dev/2009-June/021356.html
>>> - http://jira.openlaszlo.org/jira/browse/LPP-630