How to over-write the property in Ant?

Question

Is there a way to re-assign the value for the Ant property task? Or is there another task available for that purpose?

Answer 1

Here is a sample using local with the basename command. Var-unset does not work for me.

<for param="db-patches">
       <path>
            <fileset dir="${undeployed-files}" includes="**/ddl*.zip"/>
        </path>
        <sequential>
              <local name="inpfile" />
               <basename property="inpfile" file="@{db-patches}" suffix=".zip" />
               <!-- unzip the patch  -->
               <unzip src="${undeployed-files}/${inpfile}.zip" 
                   dest="${unzipped-patches}/${inpfile}" />
           <move file="${undeployed-files}/${inpfile}.zip" tofile="${deployed-files}/${inpfile}.zip"/>
        </sequential>   </for>

Answer 2

Depending on how you want to use the modified property, you can use macrodefs.

For example, instead of writing the following:

<target name="foo">
   <echo message="${my_property}"/>
</target>

and not being able to call ant foo with another message, you could write:

<macrodef name="myecho">
    <attribute name="msg"/>
    <sequential>
        <echo message="@{msg}"/>
    </sequential>
</macrodef>

<target name="foo">
   <myecho msg="${my_property}"/>
   <property name="my_property2" value="..."/>
   <myecho msg="${my_property2}"/>
</target>