-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Isaac Dupree wrote: > Simon Marlow wrote: >>> I definitely think that -1# should be parsed as a single lexeme. >>> Presumably it was easier at the time to do it the way it is, I don't >>> remember exactly. >>> >>> I'd support a warning for use of prefix negation, or alternatively you >>> could implement the Haskell' proposal to remove prefix negation >>> completely - treat the unary minus as part of a numeric literal in the >>> lexer only. This would have to be optional for now, so that we can >>> continue to support Haskell 98 of course. >>> >>> Cheers, >>> Simon > > Yes, I've been thinking about how to implement both - details will come > later when I have more time. I think I have a reasonably working idea > of how to divide up the cases for warnings for ambiguous-looking use of > both infix and prefix minus, as well as actual syntax changes...
not considering warnings, just syntax: 123abc is two valid Haskell tokens. for example: \begin{code} main = (\n c -> print (n,c)) 123Abc data Abc = Abc deriving Show \end{code} prints (123,Abc). So does this suggest that under a negation-is-part-of-numeric-token regime, 123-456 should be two tokens (a positive number then a negative number, here), as is signum-456 ... Presently, GHC doesn't even warn about the first thing (123abc) ^_^ Isaac -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.3 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFGHgT9HgcxvIWYTTURAmhLAJ0Zwd8fRYWRIWDjsTRaPx84x80RBwCgjsMA RxcCEg+2T/fraJmnsBYVEhE= =HsSp -----END PGP SIGNATURE----- _______________________________________________ Glasgow-haskell-users mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/glasgow-haskell-users