ant-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Dominique Devienne <DDevie...@lgc.com>
Subject RE: Implicit element for macrodef
Date Tue, 25 May 2004 14:20:19 GMT
> From: Peter Reilly [mailto:peter.reilly@corvil.com]
> 
> I am looking into an implementation of implicit nested elements for
> macrodef:

Cool.

>     <showfiles property="x">
>       <fileset dir="." includes="*.xml"/>
>     </showfiles>
>   </target>
> 
> The implementation does however involve a small Backward Incompatible
> change to the implementation of MacroInstance.

I'd say this is young enough that the benefits outweigh the drawbacks.

Own would implicit elements interact with nested macros, each having
an implicit element?

I personally have one request for <macrodef>: Is it possible to
determine whether an element or attribute was set in the macro
instance? Here is my use case: I have a macro that performs several
tasks, each of them using a different element of the macro. If one
of those elements is not specified in a macro instance, I'd like
to completely skip the corresponding macro task (use <ac:if> or a
builtin condition on that task). Currently, I have to define on
additional attribute on the macro to turn ON the execution of a
task, when the mere presence of the element for that task is enough
to determine whether it should run or not. Maybe something like:

<macrodef name="...">
  <element name="schemas" optional="yes" />
  <attribute name="jaxb" default="@?schemas?" />
  ...
  <sequential>
    <jaxb ... ifTrue="@{jaxb}">
      <schemas>
    </jaxb>
    ...
  </sequential>
</macrodef>

The @?element? is purely arbitrary, and just to illustrate my point.
I guess I can get by with the attribute/element twins, but I'm just
wondering if there's a way to basically discover info on the macro
instance itself, and put it to some use, as above.

Thanks, --DD

---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscribe@ant.apache.org
For additional commands, e-mail: dev-help@ant.apache.org


Mime
View raw message