Re: ghc on Win32
Matthias, I've just installed ghc-4.08 / binary release for Win32. When compiling a file Type.hs, the following happens: START Compiling Type.hs does not exist Action: openFile Reason: file does not exist /tmp/ghc1096.cpp END I had the same problem, until I read the following from http://www.haskell.org/ghc/docs/latest/set/book-users-guide.html : ## Furthermore, it seems that TMPDIR must be set to a directory in the same file system in which you invoke GHC. Otherwise you get very werid messages when you invoke GHC, such as: does not exist Action: openFile Reason: file does not exist /tmp/ghc11068.cpp We think this is due to a bug in Cygwin. ## So if your source file is in d:/src, and your TMPDIR is c:/tmp, you probably need to: cd c: path/to/ghc/bin/ghc //d/src/Type.hs -- Zhanyong Wan Dept of Computer Science, Yale University
form of class constraints
I'm using the GHC 4.08 binary distribution on Windows. According to the Haskell 98 report, class constraints are of the form C (a t1 ... tn), where C is a class, a is a type variable, and t1, ..., tn are arbitrary types (including type variables, n = 0). However, the following code failed to compile: ## module Test where newtype StateT s t b x = StateT (s - t b (s, x)) instance Functor (t b) = Functor (StateT s t b) ## Illegal constraint `Functor (t b)' in instance context (Instance contexts must constrain only type variables) I have no problem with the same code in Hugs. Is this a GHC bug? -- Zhanyong Wan Dept of Computer Science, Yale University
Time profiling interval?
While trying to generate a heap profile for a large run, I was getting lots of floating point exceptions when running hp2ps. Normally, I'd have used "+RTS -i5" (or the like) to reduce the number of samples being generated (which, I think, avoids the heap overflow and would also reduce runtime to an acceptable amount). So, the question is: how do I set the profiling interval? (btw the online users guide still documents the -i flag) -- Alastair Reid[EMAIL PROTECTED]http://www.cs.utah.edu/~reid/
