This is the mail archive of the email@example.com mailing list for the Kawa project. See the Kawa home page for more information.
I'm glad to see this discussion. Clearly, naturalness is in the eye of the beholder ... I do find: (let (((i <int>) 10)) ...) to be more natural than: (let (((<int> i) 10)) ...) Somebody mentioned that the latter is more easily parseable than the former; that is not the case. Remeber, that at least potentially we want that type-specifiers can be first-class expressions, for example a parameter of the surrounding first-class function. People who prefer either of these two variants have not commented on the fact that neither works with `define', because it would conflict with the existing function definition syntax. While we could support type specifiers without allowing them for define, I think that is a fairly serious disadvantage. This is especially the case, since I think providing all of let, let*, letrec, and internal define is poor language design, and a well-engineered language would only have some variant of internal define. (For the few times you need let or let*, you can use a lambda.) I really don't like the Common Lisp declare form. I think the type specification should be in the same place as the where the identifier is declared. (I.e. `declare' should be in the same place as the declaration!) People have suggested that VAR :: TYPE is not "Schemish". I don't see that. Scheme already has "internal" keywords ('else and '=>); I don't think adding ':: conflicts with that tradition. I still think it is easier for humans to read, less like to lead to errors, and less likely to conflict some other extension from some other Scheme dialect. What might convice me to go for ((VAR TYPE) INIT) instead of (VAR :: TYPE INIT) would be pointers to other Scheme implementation or related languages that use that syntax. The Dylan reference is an interesting note, but of course Lisp-style Dylan no longer exists. --Per Bothner Cygnus Solutions firstname.lastname@example.org http://www.cygnus.com/~bothner