Terminal does not reset correctly with System.Console.SimpleLineEditor
Hello It appears that the console is not reset correctly with System.Console.SimpleLineEditor. The terminal does not echo characters until it is reset. The following program demonstrates it: import System.Console.SimpleLineEditor main = initialise >> getLineEdited "prompt> " >>= print >> restore This occurs with the Debian ghc package version 6.2.1 and the binary cvs snapshot of 20041017, both on i386 linux and in an xterm. - Einar Karttunen ___ Glasgow-haskell-users mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
Re: Implicit parameter constraints not inferred
On Saturday 06 November 2004 17:57, you wrote: > Benjamin Franksen wrote: > > My question: Is this as it should be or is it a bug? > > The Monomorphism Restriction. Grumble... I almost suspected it. Only the context in which I got the error originally didn't _look_ as if MR would apply, and when I fumbled with the simple test program I just forgot about it. Sorry to have bothered you and thanks a lot for the answer. Your explanation of the MR is the best I've seen so far. Ben ___ Glasgow-haskell-users mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
Re: Implicit parameter constraints not inferred
Benjamin Franksen wrote: main = let ?b = True in use_b --use_b :: (?g::Bool) => IO () use_b = print ?b It isn't: ghc -fimplicit-params says Unbound implicit parameter (?b :: a) arising from use of implicit parameter `?b' at TestBug.hs:4 In the first argument of `print', namely `?b' In the definition of `use_b': use_b = print ?b It works if I uncomment the signature. Using ghc-6.2.2, btw. My question: Is this as it should be or is it a bug? The Monomorphism Restriction. It's intended to prevent people from shooting themselves in the foot by defining things that look like constants (like use_b) but really are polymorphic values that still depend on some context and therefore are not constant. So in this case (use_b defined with no arguments), you need to specify a type signature. The monomorphism restriction would be useful in situations like: foo = expensiveOp bar How often will foo be evaluated? With the monomorphism restriction, at most once. Without it, well, that depends on the type of bar. With bar :: (?g :: Bool) => Int, foo also gets the (?g :: Bool) => context, and it's reevaluated whenever it's used; but you won't be able to tell that by looking at foo alone. Cheers, Wolfgang ___ Glasgow-haskell-users mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
Implicit parameter constraints not inferred
To be fair, the ghc docs do not mention constraint inference for implicit parameters. OTOH they do not say that signatures must be given explicitly if I use implicit parameters. However, I always thought that this would be ok: > main = let ?b = True in use_b > --use_b :: (?g::Bool) => IO () > use_b = print ?b It isn't: ghc -fimplicit-params says Unbound implicit parameter (?b :: a) arising from use of implicit parameter `?b' at TestBug.hs:4 In the first argument of `print', namely `?b' In the definition of `use_b': use_b = print ?b It works if I uncomment the signature. I also tried > use_b = print (?b :: Bool) but to no avail. Using ghc-6.2.2, btw. My question: Is this as it should be or is it a bug? Ben ___ Glasgow-haskell-users mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
Re: CVS build failure
Peter Simons wrote: Linux x86, I configure my build with the script: | #! /bin/sh -- | | GHC="ghc-6.2.2" | SUBDIRS="alex ghc haddock happy hslibs libraries" | | for n in ${SUBDIRS} .; do | echo >$n/mk/build.mk "XMLDocWays := html" | done | | autoreconf -i | ./configure --prefix=/usr/local/ghc-current \ | --enable-src-tree-happy \ | --enable-src-tree-haddock \ | --enable-src-tree-alex\ | --with-ghc="${GHC}" \ | --with-hc="${GHC}"\ | --enable-hopengl \ | --disable-openal \ | ; [...] Just a small note here: Simply using make XMLDocWays=html should build everything recursively, including the HTML docs, without any need for a build.mk. Cheers, S. ___ Glasgow-haskell-users mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
Re: getUserEntryForName weirdness
Volker Stolz writes: > Fixed in CVS I've tried it moments ago: Works correctly here, too, now. Thank you. Peter ___ Glasgow-haskell-users mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
Re: proposal for ghc-pkg to use a directory of .conf files
Duncan Coutts wrote: [...] The advantage of doing this is that it makes things easier for the package managers. Each individual file can belong to the appropriate package and so instead of having to execute registration/unregistration actions on install/uninstall it's just another file to add/remove. The other advantage is that there is no longer a global file that needs to be modified which means uninstallation is cleaner (most package managers do not remove files that were modified after installation). These are exactly the reasons why e.g. the configuration files for apache2 on my SuSE Linux 9.1 are set up this way. It's very handy, clean and modular. [...] I had a peak at the code in ghc for dealing with .conf files. I'd guess it'd be best ok just check if the specified package file is a directory or an ordinary file and act accordingly. Ie you could say "-package-conf packages/" and ghc could by default read from $HC-LIB/package.conf and $HC-LIB/package.conf.d/ or something. Sounds resaonable to me. I can't see any downsides of doing it this way. I can knock up a proof of concept patch if anyone thinks this is a good idea. It should be totally backward compatible, it's ok to use both, but ditro packagers might like to enforce a policy of using a directory of package files for external libraries. OK, just send us a patch and if there are no objections we can merge it into the HEAD. Cheers, S. ___ Glasgow-haskell-users mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/glasgow-haskell-users