Is XSLT a functional programming language?

Question

Several questions about functional programming languages have got me thinking about whether XSLT is a functional programming language. If not, what features are missing? Has

Answer 1

That is not really an argument, since you can only declare variables, not change their values after declaration. In that sense it is declarative not imperative style, as stated in Mr Novatchev's article.

Functional programming languages like Scheme or Erlang enable you to declare variables as well, and in Haskell you can also do that:

-- function 'test' takes variable x and adds it on every element of list xs

test :: [Int] -> [Int]
test xs = map (+ x) xs
where x = 2