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Date: Thu, 29 Jun 2000 21:52:18 -0400
Subject: Gentle introduction to scripting
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I put a lot of power into the scripting task, a lot more than I think
people realize.  I wasn't going to discuss it until the time was right, but
now it does appear that there is enough genuine interest (trust me, it was
*very* controversial at the time).  I present it here to seed discussion -
if there are things that there is consensus on needing to be changed, then
I'm OK with change as I doubt that anybody is seriously using it.

The first thing worth mentioning is that scripts have access to everything
a Java task would have access to.  Below is an example of a simple loop
which actually modifies the build script.  Note the use of the name
"squares" and "main".

   <project name="squares" default="main" basedir=".">

     <target name="setup">

       <script language="javascript"> <![CDATA[

         for (i=1; i<=10; i++) {
           echo = squares.createTask("echo");
           main.addTask(echo);
           echo.setMessage(i*i);
         }

       ]]> </script>

     </target>

     <target name="main" depends="setup" />

   </project>

And here is the output I get when I run this script on my machine:

   Buildfile: build.xml
   Project base dir set to: C:\tmp
   Executing Target: setup
   Executing Target: main
   1
   4
   9
   16
   25
   36
   49
   64
   81
   100
   Completed in 4 seconds

- Sam Ruby