External Core tools: track new syntax for newtypes

[ghc-hetmet.git] / utils / ext-core / README

diff --git a/utils/ext-core/README b/utils/ext-core/README
index 6091935..bb5f3aa 100644 (file)
--- a/utils/ext-core/README
+++ b/utils/ext-core/README
@@ -6,20 +6,26 @@ tjc April/May 2008:
 
 ==== Notes ====
 
 
 ==== Notes ====
 

-The checker should work on most programs. Bugs I'm aware of:
-1. There's some business I don't quite understand involving
-   coercions and subkinding (for details, see:
-   http://www.haskell.org/pipermail/cvs-ghc/2008-April/041949.html)
-   This shows up when typechecking a few of the library modules.
+The checker should work on most programs. Bugs (and infelicities) 
+I'm aware of:

    
    

-2. There's some weirdness involving funny character literals. This can
+1. There's some weirdness involving funny character literals. This can

    be fixed by writing a new lexer for chars rather than using Parsec's
    built-in charLiteral lexer. But I haven't done that.
 
    be fixed by writing a new lexer for chars rather than using Parsec's
    built-in charLiteral lexer. But I haven't done that.
 

-3. When typechecking the ghc-prim:GHC.PrimopWrappers library module,
-   some declarations seem to have the wrong type signature (due to 
-   confusion between (forall (t::*) ...) and (forall (t::?) ...).)
-   This is because the ? kind is not expressible in Haskell.
+2. The test driver attempts to find module dependencies automatically,
+   but it's slow. You can turn it off with the "-n" flag to the driver,
+   and specify all dependencies on the command line (you have to include
+   standard library dependencies too.)
+     * It would help to cache dependency info for standard libraries
+       in a file, or something, but that's future work.
+
+3. To avoid implementing some of the I/O primitives and foreign calls,
+   I use a gross hack involving replacing certain standard library
+   modules with simplified versions (found under lib/) that depend on
+   fake "primops" that the Core interpreter implements. This makes it
+   difficult (if not impossible) to load optimized versions of standard
+   libraries right now. Fixing this is future work too.

 
 Typechecking all the GHC libraries eats about a gig of heap and takes a
 long time. I blame Parsec. (Someone who was bored, or understood happy
 
 Typechecking all the GHC libraries eats about a gig of heap and takes a
 long time. I blame Parsec. (Someone who was bored, or understood happy