Update.

The problem seems to be more general in that I am unable to use xacro:param
at all, which makes me think that I might be using it the wrong way. This
code also errors out :

<?xml version="1.0"?>

<robot xmlns:xacro="http://www.ros.org/wiki/xacro"
       xmlns:sensor="
http://playerstage.sourceforge.net/gazebo/xmlschema/#sensor"
       xmlns:controller="
http://playerstage.sourceforge.net/gazebo/xmlschema/#controller"
       xmlns:interface="
http://playerstage.sourceforge.net/gazebo/xmlschema/#interface"
       name="foo" >

  <xacro:parameter name="the_param" value="/path/to/foo" />
  <include filename="${the_param}" />
</robot>

Is there something obviously wrong here?. I tried grepping the ros codebase
for xacro:param occurrences to compare against, but found none.

Adolfo

2010/5/26 Adolfo Rodríguez Tsouroukdissian <dofo79@gmail.com>

> I'd like to ask whether using a xacro parameter value in xacro macros is
> allowed, because it is not clear from the docs [
> http://www.ros.org/wiki/xacro]. Consider a simplified version of my file,
> which fails on ros-latest from binary packages:
>
> <xacro:parameter name="the_param" value="1" />
>
> <xacro:macro name="macro1" >
>   <foo>${the_param}</foo>
> </xacro:macro>
>
> <xacro:macro name="macro2" params="macro2_param" >
>   <mechanicalReduction>${macro2_param}</mechanicalReduction>
> </xacro:macro>
>
>
> <xacro:macro1 />
>   <!-- Fails -->
> <xacro:macro2 macro2_param ="${the_param}" />  <!-- Fails -->
>
> The two above lines raise a XacroException that states " Property wasn't
> defined: u'the_param' " when xacro is run. Is this expected behavior?.
>
> TIA,
>
> Adolfo
>
>
> --
> Adolfo Rodríguez Tsouroukdissian, Ph. D.
>
> Robotics engineer
> PAL ROBOTICS S.L
> http://www.pal-robotics.com
> Tel. +34.93.414.53.47
> Fax.+34.93.209.11.09
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