Dennis Lee Bieber wrote: > On 26 May 2005 17:33:33 -0700, "Elliot Temple" <[EMAIL PROTECTED]> > declaimed the following in comp.lang.python: > >> Thanks for the link on case sensitivity. I'm curious about the person >> who found case sensitivity useful though: what is it useful for? >> > Making a language run faster on slow machines since the syntax > parsing doesn't have to do the equivalent of upper or lower casing > anything that is not a string literal before checking for keywords or > identifiers. > > Consider the time spent by languages like Ada and Fortran when > they have to do case normalization every time you compile. > That isn't a good argument for case sensitivity. You really aren't going to be able to measure a slowdown in compilation speed just because the compiler has to lowercase all the identifiers before using them.
What I consider good arguments for case sensitivity are: Consistency. I've used non-case sensitive languages where the same variable was spelled sometimes with capitals and sometimes without. Forcing you to choose one case and stick to it is, IMHO a good thing. Worse, I've used Visual Basic where the editor will gratuitously change the case of a variable you just typed in because there is another occurrence of the same name somewhere else in a different case. Conventions such as capitalising class names, or camelCasing can be useful. Again this only applies if they are used consistently. Interoperability. Like it or not, there are other case sensitive systems out there. I once had the misfortune to use a Microsoft Access database (where lookups on indexed fields are case insensitive) to store records indexed by a case sensitive medical coding system. Codes in that system do exist which differ from other completely unrelated conditions only by the case of the code. The only way to handle this in a case insensitive system is to somehow escape each case sensitive code. That particular example wouldn't necessarily apply to a case insensitive programming language, but plenty of others would: e.g. using a remote procedure call system to call a (case sensitive) function on another system. In all such cases, the case insensitive system is the 'poor relation', it is the one where you have to introduce workrounds in order to communicate with the case sensitive system. Going in the other direction (calling a case insensitive function from a case sensitive system) you simply have to invent a convention (e.g. lowercase everything) and stick by it. There are arguments that, especially for beginners, case sensitivity introduces an extra level of complexity, but the cost of losing this complexity would be to make Python a poor relation amongst programming languages. -- http://mail.python.org/mailman/listinfo/python-list
