[Hat] Problems building Hat on Mac OS X

[Malcolm Wallace]

Stephen Pitts <smpitts@ou.edu> writes:

> I'm once again trying to build Hat; this time it's on Jaguar with GHC 
> 5.04.2. I got past the first problem; as someone else pointed on in the 
> archives, HFS+ has some interesting case sensitivity issues, so I had 
> to invoke ghc to compile Hat.hs by hand.

In the next release, we have renamed files to avoid case insensitivity
problems.

> After that, the build seemed to be going OK until I got this message:
> /usr/local/src/hat-2.00/script/hat-trans -trusted -prelude 
> PreludeTracing.hs
> 
> Fail: Cannot parse in .hx file PreludeBasic line (Var "seq",Value 
> {args=-1, fixity=R, priority=0, letBound=True})

The problem is that "args=-1" is being lexed internally as the token
sequence: args =- 1.  In fact the field value should really have been
written in the first place as either "args=(-1)" or "args = -1", and
the fault is with the compiler-derived show instance for this datatype.
Although ghc-5.04.1 had this bug, but was supposed to have been fixed
in 5.04.2.  Indeed 5.04.2 works fine under Linux here, so I have no
idea why you are seeing the problem recur under MacOS-X.

So the best answer I can suggest is to check whether you really do
have ghc-5.04.2, and if so, enquire with GHC central about why it
appears to omit this bugfix.  You could also try upgrading to 5.04.3
(a MacOS-X binary bundle is not yet available, but you could build
it from source).

Incidentally, we plan to release hat-2.02 very soon, but it probably
won't make any difference to this particular problem, because it is
your copy of ghc, not Hat, which is at fault.

Regards,
    Malcolm