> I used the XML/XSL snippet below. However the "@key eq ." 
> seems not to work.
> 
> If I introduce a variable it works fine:
> 
>     <xsl:variable name="var" select="."/>
>     <xsl:value-of select="$map[@key eq $var]/@val"/>

"." within a predicate refers to the node that you are testing against the
predicate. This is the problem with context dependency - it's nice and
convenient when it does what you are expecting, and it's a rich source of
bugs when it doesn't.
> 
> Questions:
> 
> 1. How to get this mapper working without variable?

You could use current(), but I'd be inclined to use the variable.

> 2. What is the the 'defacto XPath standard' for mapping  a 
> list hardcoded keys to hardcoded values?

The above is fine - though in XSLT, unless you have a processor with an
unusually good optimizer, like Saxon-SA ;-), you can speed it up using keys.

Michael Kay
http://www.saxonica.com/