Syntax extensions

[Isaac Jones]

I don't mind pointing out that either solution, compiler independent
pragmas or extension import lists, would be great for the Library
Infrastructure Project, since it will save us from having to include
per-file command-line flags in a package configuration database (see
my message to libraries@haskell.org from yesterday).

Also I've mentioned several times that I think it would be great if we
had another flag which turned on the features that are shared between
the major Haskell implementations.

So for each implementation, there would be three modes, haskell98,
kitchen-sink, and shared-options, the last of which turns on
extentions like multi-param type classes and hierarchical modules that
are implemented in a standard way.

This way, the user can tell that they're writing mostly portable code
(though with no guarantees as to future compatibility).  It also could
possibly be used as a staging ground for the next version of Haskell
once there's a "feature freeze".

peace,

isaac