- Glasgow-haskell-users

happy and OPTIONS pragmas
by Ian Lynagh 04 Nov '04

04 Nov '04

Hi, If I have this at the start of a .x file: { {-# OPTIONS -w #-} module Lexer (lex_tok) where } then the generated .hs file starts: {-# OPTIONS -cpp #-} {-# LINE 2 "Lexer.x" #-} {-# OPTIONS -w #-} module Lexer (lex_tok) where and the warnings are suppressed when I compile my program with ghc -Wall --make However, if a .y file starts: { {-# OPTIONS -w #-} -- Foo {-# OPTIONS -w #-} module Parser (parse) where } then the generated .hs file starts: -- parser produced by Happy Version 1.14 -- Foo {-# OPTIONS -w #-} module Parser (parse) where so the pragma before my comment has been eaten and the 2 comments mean that ghc doesn't see the pragma, so gives me all the warnings anyway. Can happy be changed so my pragma gets through please? Thanks Ian, with happy 1.14

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GHC bug typo...
by Keean Schupke 03 Nov '04

03 Nov '04

obviously I meant: type a :+ b = (a,b) In that last post!

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GHC CVS HEAD bug!
by Keean Schupke 03 Nov '04

03 Nov '04

The CVS HEAD branch of GHC seems to ignore the fixity of type constructors imported from another module... This breaks compiling of code that uses this feature: module1: type a b = a :+ b infixr 1 :+ module2: a :: Int :+ Float :+ Double a = undefined Gives a the wrong type. Keean

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GHCI and readline package
by Wassell, Mark P (GE Energy) 02 Nov '04

02 Nov '04

Hi, I'm having a problem running ghci and loading the readline package on WindowsXP. C:\Software\haskell\ghc622\bin>ghci -package readline ghci -package readline ___ ___ _ / _ \ /\ /\/ __(_) / /_\// /_/ / / | | GHC Interactive, version 6.2.2, for Haskell 98. / /_\\/ __ / /___| | http://www.haskell.org/ghc/ \____/\/ /_/\____/|_| Type :? for help. Loading package base ... linking ... done. Loading package readline ... linking ... C:/Software/haskell/ghc622/HSreadline.o: unknown symbol `_rl_redisplay_function' ghc.exe: unable to load package `readline' I have seen the follow in the user guide: "For some reason, Mingw ships with the readline library, but not with the readline headers. As a result, GHC (like Hugs) does not use readline for interactive input on Windows. You can get a close simulation by using an emacs shell buffer!" but I assume I need readline as util needs it and util is needed by data which is needed by wxcore. Cheers Mark

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GHC 6.2.2 on Linux with glibc2.2
by George Russell 02 Nov '04

02 Nov '04

I've put a compiled version of ghc6.2.2 for Linux machines still using glibc2.2 on http://www.informatik.uni-bremen.de/~ger/ghc In fact it should work on glibc2.3 as well, thanks to a minor hack from Christian Maeder. Documentation is not complete, but does at least include HTML.

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Is it safe to call getProcessExitCode more than once?
by Peter Simons 30 Oct '04

30 Oct '04

What will happen if I call getProcessExitCode for the same process twice? Will that block? Cause an error? Or return the same child's exit code again? I assume the function is (under Unix) based on wait(2), right? In that case, how does the following warning from the manual page translate to Haskell? ERRORS ECHILD if the process specified in pid does not exist or is not a child of the calling process. (This can happen for one's own child if the action for SIGCHLD is set to SIG_IGN. See also the LINUX NOTES section about threads.) The reason I am asking is because I want to avoid zombie processes by doing a "catch-all" getProcessExitCode for every process I spawn through a finalizer. I'd just like to know whether it's safe before I do it. :-) Peter

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Syntax error in happy/doc/happy.xml
by Peter Simons 30 Oct '04

30 Oct '04

Index: happy/doc/happy.xml =================================================================== RCS file: /cvs/fptools/happy/doc/happy.xml,v retrieving revision 1.7 diff -b -u -r1.7 happy.xml --- happy/doc/happy.xml 29 Oct 2004 08:26:53 -0000 1.7 +++ happy/doc/happy.xml 30 Oct 2004 12:18:32 -0000 @@ -1777,11 +1777,11 @@ <para> There is some support for monadic parsers. The "tree decoding" mode - (see <xref linkend="sec-glr-semantics-tree">) can use the + (see <xref linkend="sec-glr-semantics-tree"/>) can use the information given in the <literal>%monad</literal> declaration to monadify the decoding process. This is explained in more detail at - <xref linkend="sec-glr-semantics-tree-monad">. + <xref linkend="sec-glr-semantics-tree-monad"/>. </para> </listitem> </varlistentry>

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Calling Haskell from .Net
by David Lo 28 Oct '04

28 Oct '04

Dear all, I'm new in Haskell. I need to port a haskell application written by someone else to be called by a .Net C# application. Please kindly advise on which option to pursue. Maybe on how to convert haskell code to dll or how to let C++ code (in dll format) to call Haskell. Any helps will really be appreciated. Best Regards, David

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Patchy GHC support for a week
by Simon Marlow 28 Oct '04

28 Oct '04

Just to let everyone know that Simon PJ and myself will be away for the rest of this week and the next, and will probably have intermittent network connectivity, so it might take us a while to respond to messages. Cheers, Simon

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--make et al not in flags.sgml?
by Ian Lynagh 27 Oct '04

27 Oct '04

Hi, Is there a reason --make and friends aren't in flags.sgml? This means they don't end up in the man page I generate. I've attached a patch that adds an entry for them, text mostly stolen from elsewhere in the docs. Thanks Ian

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