Path: utzoo!attcan!uunet!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!rpi!clarkson!news.clarkson.edu!cline From: cline@cheetah.ece.clarkson.edu (Marshall Cline) Newsgroups: comp.object Subject: Re: Do we really need types in OOPL's? Message-ID: Date: 1 Oct 90 21:46:07 GMT References: <0yw10qr@Unify.Com> <411@eiffel.UUCP> <736@tetrauk.UUCP> <1990Sep25.135145.3460@kth.se> <3832@osc.COM> Sender: news@news.clarkson.edu Reply-To: cline@sun.soe.clarkson.edu (Marshall Cline) Organization: (I don't speak for the) ECE Dept, Clarkson Univ, Potsdam, NY Lines: 32 In-Reply-To: tma@osc.COM's message of 27 Sep 90 08:06:20 GMT Nntp-Posting-Host: cheetah.ece.clarkson.edu In article <3832@osc.COM> tma@osc.COM (Tim Atkins) writes: ... > I also disagree that "strong" typing cannot be simulated in a >dynamically typed language. Type or even protocol tests can be inserted at >will and could probably be automated in fairly clever and efficient fashion. This reveals probably the most common communication problem: nomenclature. What is usually meant by ``strong'' typing is ``static'' typing (cf. Booch OOD, Meyer OOSC, etc). Ie: saying that an OOPL is strongly typed means things like: the compiler can tell, from the *text* of the program alone, whether or not an object will be equipped to handle a particular message. Strong (static) typing does *NOT* mean the compiler knows what the message will *do*, the latter being static binding. Static binding says the compiler knows (from the text of the program alone) the exact member function that will be called. Dynamic binding and static typing coexist wonderfully, existence proofs being C++, Simula, Eiffel, etc. Strong typing is especially valuable for programming-in-the-large where the edit-compile-debug cycle is especially tedious. All other things being equal (they're not), ``sooner'' error detection is better than ``later''. Marshall Cline -- ============================================================================== Marshall Cline / Asst.Prof / ECE Dept / Clarkson Univ / Potsdam, NY 13676 cline@sun.soe.clarkson.edu / Bitnet:BH0W@CLUTX / uunet!clutx.clarkson.edu!bh0w Voice: 315-268-3868 / Secretary: 315-268-6511 / FAX: 315-268-7600 Career search in progress; ECE faculty; research oriented; will send vita. PS: If your company is interested in on-site C++/OOD training, drop me a line! ==============================================================================