Circuralizing lists

["Till Varoquaux" <till.varoquaux@gmail.com>]

Writing the list containing an inifinite number of ones can easily be done as:

let rec ones = 1::ones

I however don't know of any type safe to generate the infinite list
which is the repetition of a given list (in a type safe non lazy way).
What I'm looking for is a code that would do:

let circularize  = function
    | [] -> failwith "cannot circularize empty lists"
    | l -> let rec res = l@res in res

Is this at all possible?

Cheers,
Till