Constructors are not functions

[Chantal KELLER <chantal.keller@wanadoo.fr>]

    Dear Ocaml users,

  Is there a reason for constructors not to behave like functions? For
instance, one cannot make a partial application from a constructor:

# type foo = | Bar of int;;
type foo = Bar of int
# let foobar = Bar in foobar 17;;
Error: The constructor Bar expects 1 argument(s),
       but is applied here to 0 argument(s)

  Thanks,
-- 
Chantal KELLER