On 2004-11-17, Vincenzo Ciancia
On Tuesday 16 November 2004 10:37, Henning Thielemann wrote:
Variable length argument lists are really a mess. Why are people so keen on them? What is the advantage over a plain list as single argument? Is vsprintf "%s, your age is %s\n" ["John", show (10::Integer)] really too complicated?
The implementation of printf in ocaml, for example, is not only type-safe, but "more type safe" than passing a list, because the number and type of arguments is known at compile time.
On the other hand, the OCaml printf is, unless I'm very mistaken, handled specially by the compiler. That is, the compiler looks out for format strings and converts them to the weirdo format4 things that OCaml uses. That means that one could not implement one's own printf using pure OCaml. Though a person could use camlp4, but then that's back to the same place as TH. OCaml's printf also is limited in that it can take only a string literal for the format string, and not a string in a variable. -- John