root/trunk/ProjectFortress/demos/fact64.fss

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component fact64
export Executable

(* Computing factorial, in 64 bits.  Notice the call to "widen";
   this is necessary at least with the current interpreter, which 
   otherwise cheerfully multiplies two 32-bit integers giving a 32-bit
   result, in a way that would not surprise Kernighan and Ritchie
   in the least. *)

run() = do 
   for i <- seq(0#20) do
     j:ZZ64 = widen(i)
     println("fact(" j ")= " f(j))
   end
end

f(x:ZZ64):ZZ64 = if x < 2 then 1 else x f(x-1) end
end