Bugs

[Simon Marlow]

Hugs folk,

I thought I'd run the latest Hugs against some of the GHC tests, in
particular to test the module system since it's received some attention
recently.  I've found a few bugs...  all these test cases can be found
under fptools/testsuite/rename.

1. Hiding constructors doesn't work properly.  See rename/prog002, which
should fail to compile.

2. Pattern bindings which bind no variables are erroneously disallowed
(rename/should_compile/rn003).

3. some problem with qualified imports (rename/should_compile/rn026 and
rename/should_compile/rn027).

4. defining a variable which clashes with an import is ok as long as the
variable is never referred to.  Hugs disallows it.
(rename/should_compile/rn029).

5. some problem with empty declaration lists
(rename/should_compile/rn034).

6. infix declarations are legal inside a class declaration
(rename/should_compile/rn035).

7. precedence parsing with unary negation is wrong.
(rename/should_fail/rnfail017.hs).

8. it appears that extra qualified names are being brough into scope
(rename/should_fail/rnfail030.hs and rnfail031.hs).

9. hiding doesn't work with qualified imports
(rename/should_fail/rnfail032.hs and rnfail033.hs).

10. naming a constructor in an export list is illegal.
(rename/should_fail/rnfail035.hs).

We really ought to think about merging our test suites at some point;
the stuff in fptools/testsuite is supposed to be largely
compiler-independednt, but it will need some work to make it go through
with Hugs.

Cheers,
	Simon