> let string_list_of_chann chann =
>   let rec slof_aux (ch: in_channel) (l: string list) = 
>     try
>       let readstr = input_line ch in
>       slof_aux ch readstr::l
>     with End_of_file -> l
>   in slof_aux chann []
> 
> and the error is:
> 
> File "query.ml", line 11, characters 19-155:
> This expression has type in_channel -> string list -> string list
> but is here used with type in_channel -> string -> string
> make: *** [all] Error 2
> 
> 
> Is this a problem with relying on an exception to type a function?

No, your problem is just parsing: you should write

 slof_aux ch (readstr::l) instead of slof_aux ch readstr::l

since in Caml, function application binds tighter than operations,
that is, for all binary infix operator op

f x op z means (f x) op z

Pierre Weis

INRIA, Projet Cristal, Pierre.Weis@inria.fr, http://pauillac.inria.fr/~weis/