What does a pipe (|) do in a CSS selector?

Question

I found the following definition in a CSS stylesheet :

*|*:link {color:#ff00ff;}

What\'s the use of the |? Is it

Answer 1

It separates namespace and element name.

Unless a default namespace has been defined, *|*:link is a complicated way of writing *:link or just :link.

In an XML document, you could have the following:

<el xmlns="http://name/space" />
<style>
@namespace namespace_example url(http://name/space);
namespace_example|el {background: red;}
</style>

Answer 2

It is used with namespaces, defining the namespace|element. For more information, have a look at the documentation here. If there is no namespace defined, it is pointless to define the selectors with namespace *.