[Laszlo-dev] defining classes in any order in LZX

[P T Withington]

I thought Henry's question was with regard to the tag compiler.

Doing it in the script compiler would be a bonus, but it would not  
solve the issue Henry was hitting.  The tag compiler currently  
requires the super model to exist.

On Feb 11, 2009, at 17:40, Donald Anderson <dda at ddanderson.com> wrote:

> Are you suggesting we handle this in the tag compiler?  Are there  
> advantages to that?
> Might be useful to have the capability in lzs code too.
>
> - Don
>
> On Feb 11, 2009, at 5:29 PM, P T Withington wrote:
>
>> This should be fairly easy. We already allow forward references to  
>> classes when instantiating them. It would just mean delaying  
>> completing the model until you need it, rather than at the time you  
>> parse it.
>>
>> On Feb 11, 2009, at 16:22, Henry Minsky <henry.minsky at gmail.com>  
>> wrote:
>>
>>> Currently the way the LZX compiler works, this code gives an error
>>> "undefined superclass foo for class bar"
>>>
>>> <class name="bar" extends="foo"/>
>>> <class name="foo"/>
>>>
>>>
>>>
>>> because the compiler parses classes internally in the lexical order
>>> they occur in the source, and foo is not defined
>>> yet when it tries to compile bar.
>>>
>>> However, we could make the compiler do a pass that stores the class
>>> declarations and parses them on demand
>>> so that the order you declare them lexically doesn't matter.
>>>
>>> I guess we've gotten this far without the compiler doing this for  
>>> you,
>>> but I'm wondering if it would
>>> be a useful thing to do, considering that other object oriented
>>> languages generally seem to allow
>>> it.
>>>
>>> -- 
>>> Henry Minsky
>>> Software Architect
>>> hminsky at laszlosystems.com
>
>
> --
>
> Don Anderson
> Java/C/C++, Berkeley DB, systems consultant
>
> voice: 617-306-2057
> email: dda at ddanderson.com
> www: http://www.ddanderson.com
>
>
>
>
>
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