Josef Svenningsson: > I'm in favour of changing the comment syntax. > > On 2/2/06, Manuel M T Chakravarty <[EMAIL PROTECTED]> wrote: > I am against such a change. The change would break existing > software > (eg, Yampa) and secondly I don't buy the "main sources of > confusion for beginners" argument. The confusion arises only > when a > single line comment is used to uncomment a set of characters > that start > with a special symbol. That's a situation that doesn't arise > that > often. (I'd actually be very happy if the main sources of > confusion fpr > beginners where of such simple syntactic nature.) > > Oh yes, it does happen that a single line comment begins with a > special symbol. It has happened to me on several occations when using > haddock annotation to my source code. It is all to easy to forget that > extra space. With incomprehensible error messages as a result.
I didn't say it doesn't happen. I said, it doesn't happen that often. Haddock increases the likelihood of it happening, but as Henrik wrote, well just improve the errors messages a bit. Errors involving operators starting with -- could specifically suggest that the user might have wanted a comment, but wrote an operator. > As for consistency, well if you absolutely want to make it > consistent, > impose the same rule on {- as on --. > > I still think there is an inconsistency here. And it has to do with > maximal munch lexing. Maximal munch is what we normally expect from a > lexer for a programming language. But the way comments work at the > moment breaks maximal munch. The longest possible read is to read the > whole line as a comment and not interpret for instance --^ as an > operator. It breaks any programmers' intuition not only beginners'. I > still get it wrong from time to time. That doesn't convince me either. Comment syntax breaks standard lexical analysis for nested comments anyway (as they are not regular). And as I wrote before, if we were to design a language from scratch, I might be persuaded to change my opinion, but if we change the rule for Haskell now, we break good code. I believe, we should not break good code without a really good reason. I haven't seen a really good reason to change the status quo. Manuel _______________________________________________ Haskell-prime mailing list Haskell-prime@haskell.org http://haskell.org/mailman/listinfo/haskell-prime