Crawling a javascript variable inside HTML file with web-harvest!

[Júlio Adrian M Van Helden]

I have a question (dummy maybe). Suppose that I have the following snippet
of code inside an html page with a bunch of other things (other script tags
and html tags):

<script type="text/javascript">
    var count = 0;
    var active = false;
    var mapData = *{"points":

[{"type":"origin","name":"6003","lnglat":"174.77851504231018,-41.278763329010459,0\n"}]}
*;
</script>

And I would like to scrape only the content of mapData variable (which is
in bold in the example above).

I am struggling with the xpath expression that I need to use in my xml
configuration file to get only the mapData variable content. As I am new
with XPath/Web-harvest, I am not sure if the solution is using xpath
expression or maybe other approach (the web harvest script tag).

All the other times I have based my scraping on HTML tags and the name of
the id attribute inside it, but now I only have a lot of script tags inside
the file and I need to get the mapData variable.

Any thoughts?