& XSLT I'm trying to find a value in an XML document using XPATH.  I want to use a variable 
that contains the path because I will be looping through several paths and passing them to a
 method.  Is this valid?
 
##$browser is an LWP::UserAgent object
my $URL = "$protocol\://$host:$port/sdk/$parent?ip=$ip";
my $response = $browser-> get($URL);

$searchPath="chassis/ramMemory/size";
my $parser = XML::XPath::XMLParser-> new(xml => $response->content);
my $root_node = $parser-> parse;
my $xp = XML::XPath-> new(context => $root_node);

###Is there a way to make the following work?  
my $nodeset=$xp-> find('$searchPath[@value]');
 
###Rather than:
my $nodeset=$xp-> find('chassis/ramMemory/size[@value]');

The errror I am getting is:
Can't call method "isa" on an undefined value at C:/Perl/site/lib/XML/XPath/Expr.pm line 142
.
 
Any pointers would be greatly appreciated.
 
Thanks,
Amanda