1 Changes made since 2.10:
5 \item Multi-parameter type classes are fully implemented. There is more
6 sharing of dictionaries than in 2.10, so there's a chance that
7 efficiency will increase a little too.
9 \item Error messages from the type checker should be noticeably improved
11 \item Warnings for unused bindings @-fwarn-unused-names@.
13 \item The "boing" example works, and many other minor bug fixes.
15 \item Can only be built with 2.10 or later; committed to Haskell 1.4
16 module system and libraries. Much cruft removed as a result.
18 \item Dramatic clean-up of the @PprStyle@ stuff. No explicit "sty"
19 parameters now; it's all handled under the hood in @Outputable.lhs@.
21 \item The type @Type@ has been substantially changed. Usage types have
22 gone away entirely. Type is parameterised wrt the "flexi" slot
23 in type variables, rather than wrt the type variable itself.
24 That means that many instance decls become much simpler, because
25 they are polymorphic in the "flexi" slot rather than needing
26 (say) @Outputable@ on the type variable.
28 \item The dictionary for each class is represented by a new
29 data type for that purpose, rather than by a tuple. That in
30 turn means that @Type@ can be a straightforward instance of @Eq@ and
31 @Ord@ No need for @eqSimpleTy@, @eqTy@.
33 \item The resulting compiler is just slightly (2%) shorter than the
34 old one in terms of source code size.
36 \item Fix bug in posix signal handling.
38 \item @Int@ and @Word@ rewritten to use unboxed types and operations.
40 \item Removed @ghc/Error.{lhs,hi-boot}@
42 \item Moved contents of @Error@ to @GHCerr@ + adjusted
43 import lists of files that use old Error functionality.
45 \item Moved @seqError@ from @Prelude@ to @GHCerr@.
47 \item Fix a misleading type checker error msg.
49 \item Fix a bug in @floatBind@ in @Simplify.lhs@
51 \item Better failure message when entering an unimplemented instance method
53 \item The Installation Guide is now in SGML format. SGML-Tools 1.0.3
54 or later are required (check @http://www.xs4all.nl/~cg/sgmltools/@).
55 The index generation isn't automatic yet, but will hopefully be fixed