Bruno Desthuilliers <[EMAIL PROTECTED]> wrote: ... > I still maintain that the primary *practical* reason behind static > typing is to provide optimization clues for the compiler. You can (or at
It's definitely a helpful aspect, yes -- given that compilers able to infer types are still not very common for widely used languages; also, complete type checking or inference requires analysis of the whole program, which may be quite impractical -- and stops what Van Roy and Haridi, in their masterpiece "Concepts, Techniques and Models of Computer Programming", call "totally open programming". Quoting a post of mine from 2004: """ I love the explanations of Van Roy and Haridi, p. 104-106 of their book, though I may or may not agree with their conclusions (which are basically that the intrinsic difference is tiny -- they point to Oz and Alice as interoperable languages without and with static typing, respectively), all the points they make are good. Most importantly, I believe, the way dynamic typing allows real modularity (harder with static typing, since type discipline must be enforced across module boundaries), and "exploratory computing in a computation model that integrates several programming paradigms". "Dynamic typing is recommended", they conclude, "when programs must be as flexible as possible". I recommend reading the Agile Manifesto to understand why maximal flexibility is crucial in most real-world application programming -- and therefore why, in said real world rather than in the more academic circles Dr. Van Roy and Dr. Hadidi move in, dynamic typing is generally preferable, and not such a tiny issue as they make the difference to be. Still, they at least show more awareness of the issues, in devoting 3 excellent pages of discussion about it, pros and cons, than almost any other book I've seen -- most books have clearly delineated and preformed precedence one way or the other, so the discussion is rarely as balanced as that;). """ > least could) have declarative static typing with very few type > *checking* - I may be wrong here but I think one could even write a C > compiler without *any* type checking. Heck, the programmer said it's a > char*, so it must be one, right ?-) That compiler, I believe, would violate the ISO standard for C (so calling it a "C compiler" would be about as correct as calling it a banana, in my view:-). > wrt/ proofs of correctness, I'll just point to the spectacular failure > of Ariane, which was caused by a *runtime* type error in a system I like a quote by Knuth -- "beware this program may have bugs as I have only proven it and not tested it":-) > Hmmm... For a dinausor, C seems well alive. Can you remind me which So do chickens. Alex -- http://mail.python.org/mailman/listinfo/python-list
