Ant antcall a target that defines a property - ant

Question

In Ant I want to define a target (called A) that define a property and antcall it from another target (called B). I want that the target B, after antcalling the target A, can access the property defined in the target A.
For example:
<target name="B">
<antcall target="A" inheritAll="true" inheritRefs="true" />
<echo>${myprop}</echo>
</target>
<target name="A">
<property name="myprop" value="myvalue" />
</target>
However it doesn't work and <echo>${myprop}</echo> doesn't print myvalue (I think because the property myprop isn't defined in B).
Is there any way to do that?

Answer 1

According to the Apache Ant FAQ:
<target name="cond" depends="cond-if"/>
<target name="cond-if" if="prop1">
<antcall target="cond-if-2"/>
</target>
<target name="cond-if-2" if="prop2">
<antcall target="cond-if-3"/>
</target>
<target name="cond-if-3" unless="prop3">
<echo message="yes"/>
</target>
Note: <antcall> tasks do not pass property changes back up to the environment they were called from, so you wouldn't be able to, for example, set a result property in the cond-if-3 target, then do <echo message="result is ${result}"/> in the cond target.
In this respect, it is impossible to do what you want using antcall.
========== edit ===========
Try antcallback: AntCallBack is identical to the standard 'antcall' task, except that it allows properties set in the called target to be available in the calling target.
http://antelope.tigris.org/nonav/docs/manual/bk03ch20.html
Sample code pasted from the above page:
<target name="testCallback" description="Test CallBack">
<taskdef name="antcallback" classname="ise.antelope.tasks.AntCallBack" classpath="${antelope.home}/build" />
<antcallback target="-testcb" return="a, b"/>
<echo>a = ${a}</echo>
<echo>b = ${b}</echo>
</target>
<target name="-testcb">
<property name="a" value="A"/>
<property name="b" value="B"/>
</target>

Answer 2

Another approach is to refactor your targets into macros. You are trying to use targets like functions and they are just not intended to be used that way. I typically write the bulk of my logic as macros, so that I can compose it more easily into more complicated macros. Then I write simple wrapper targets for the command-line entry points that I need.

Answer 3

Rather than using <antcall>, why not just have target B depend on target A?
<target name="B" depends="A">
<echo>${myprop}</echo>
</target>
<target name="A">
<property name="myprop" value="myvalue" />
</target>

Answer 4

I think you want to use a param.
<project default="B">
<target name="B">
<antcall target="A">
<param name="myprop" value="myvalue"/>
</antcall>
</target>
<target name="A">
<echo>${myprop}</echo>
</target>
</project>
I surrounded this with a project tag and moved the echo statement into "A". My output says
B:
A:
[echo] myvalue
BUILD SUCCESSFUL

Answer 5

#alem0lars, since you said you would like to subdivide a target, let me offer a different solution (that unfortunately doesn't answer your original question).
<project default="mytarg">
<target name="mytarg">
<property name="tgt" value="build"/>
<antcall target="deps"/>
</target>
<target name="deps" depends="aTgt,bTgt"/>
<target name="aTgt">
<echo>"In aTgt doing a ${tgt}"</echo>
</target>
<target name="bTgt">
<echo>"In bTgt doing a ${tgt}"</echo>
</target>
</project>
This subdivides the build into aTgt and bTgt.
Output will be
aTgt:
[echo] "In aTgt doing a build"
bTgt:
[echo] "In bTgt doing a build"
deps:
BUILD SUCCESSFUL