On Wed, Aug 24, 2011 at 7:01 PM, Philippe Veber <[email protected]> wrote:
>> The following fragment compiles without a warning but produces strange >> results: >> >> let f ?(p1="p1") ~p2 p3 = >> Printf.printf "p1=%s, p2=%s, p3=%s\n" p1 p2 p3 >> >> let _ = >> f "p2" "p3"; (* 1 *) >> let f2 = f "p2" in >> f2 "p3" (* 2 *) (...) > This first application also applies optional arguments situated before the > anoymous argument, so it remains the second (labeled) argument only. > > There is indeed a special case where you can drop labels if you provide the > exact number of arguments. This means that f "p2" "p3" is equivalent to f > ~p2:"p2" "p3". This is written in the manual > (http://caml.inria.fr/pub/docs/manual-ocaml/manual006.html) : > > "As an exception to the above parameter matching rules, if an application is > total, labels may be omitted. In practice, most applications are total, so > that labels can be omitted in applications. " > > So this is actually the intended behavior, AFAIU Indeed. Thanks for the detailed explanation. But shouldn't the compiler decide that the partial application skipping labeled parameter is suspicious and generate a warning? - Dmitry Bely -- Caml-list mailing list. Subscription management and archives: https://sympa-roc.inria.fr/wws/info/caml-list Beginner's list: http://groups.yahoo.com/group/ocaml_beginners Bug reports: http://caml.inria.fr/bin/caml-bugs
