Re: [jelly] XMLOutput.data(Object)

[Paul Libbrecht]

Le 7 oct. 04, � 02:23, Dion Gillard a �crit :
On Wed, 6 Oct 2004 15:18:50 +0200, Paul Libbrecht 
<[EMAIL PROTECTED]> wrote:
Gee... I was really thinking this was obvious... hence the relatively
undetailed descriptions.
Obviously it isn't for me. It seems to me that you want to use
XMLOutput to pass data around, even though it's currently a
'write-only' object, i.e. there's no way of getting of data back out
of it.
The read-write paradigm is really old fashioned.
What I have in my component-tag inside the invokeBody(xmlOutput) is 
(with a simplification):

  super.invokeBody(new XmlOutput(xmlOutput) {
    public void objectData(Object b) {
        if(b instanceof Component) {
          addChild(b);
        }
      });
That's not really reading or writing, it's just catching!
- XMLoutput objects are exchanged as part of the doTag nested calls.
Therefore it is easy for something aimed at "receiving data" to create
an XMLOutput object that does something just for the data() call, and
passes-through for the rest.
This way a tag can receive a return value.
There's no way to do so with the context except delicate hacks and
fragile naming-conventions.
Sounds like hand-waving. Obviously tags return values, e.g. the set 
tag.
Tags don't return values, tag only write values in the context.
A returned value could be used in further functional composition.
Further composition of a value in the context needs to name it (and 
manage its deletion in some way).

Isn't the context for passing stuff around?
Same.
- to me, it makes loads of sense to have tags that transform their
output... and that should apply to object-data as well. (so that 
adding
a constraint in jelly-swing would be simply a transformation)
Tags that transform their own output? Or output from nested tags?
output of nested tag.
At least, to me, it is the only way for a component child, like a 
swing button, to talk flexibly to a component container, without 
manually walking the hierarchy.
Hmmm. *Only* way seems to be a little exaggerated. Can't the component
have it's parent set at some time later?
Well, I really tried hard in all sorts of way and didn't manage it.
The notion of parent is not well defined if you want to re-use 
scripts-snippets...

paul
---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]