- Hugs-Bugs - Haskell.org

Forall quantified record fields.
by Ulf Norell 29 Jul '02

29 Jul '02

Hugs will produce funny looking results when using forall quantified fields in records. For instance newtype Foo = Foo { foo :: forall a. a -> a } Main> foo (Foo {foo = id}) 42 Foo_Foo id 42 Main> $$ + 1 INTERNAL ERROR: Bignum expected Main> foo (Foo {foo = id}) 42 + (1 :: Int) 1 Main> foo (Foo {foo = id}) True Program error: {instShow_v81_v1123 0 (Foo_Foo id Bool_True)} Everything works fine though, if you don't use the record update syntax: Main> foo (Foo id) True True / Ulf Norell

1 0

BUG in input.c
by Menaka Lashitha Bandara 29 Jul '02

29 Jul '02

Hi Guys, Here's a patch for a bug that was uncovered on my machine. Hugs did work for some time, and then suddenly stopped working (ie, wouldn't Parse Prelude.hs, and eats up CPU). Basically, lineBuffer in input.c was declared type (char), and EOF on my machine is -1, so it's outside the range of (char). The bug occurs line 516 of input.c (original). It works ok on x86, so I've put a little preprocessor routine to adapt depending on the value of EOF. There's one of my comments there, and if you feel that it taints hugs code, feel free to remove it. Take care, keep up the good work :). \LaShI -- Debian GNU/Linux 3.0 (Sid) (ibook2,powerpc), kernel 2.4.18-benh-xfs <lashi(a)optusnet.com.au> 1874 5597 C754 5209 0A7D 4DA6 9112 5D0E CC1F 67BC

1 0

An Urgent Request for Help -- Problem in doing the installation of Hugs.
by krishnan raman 26 Jul '02

26 Jul '02

July 25, 2002 HUGS people: I would greatly appreciate your help in getting HUGS installed properly very soon. BACKGROUND: 1) My system: Pentium PC with WIN NT 4 -- plenty of disk space and RAM. [ After I get this right, I will have to do the same in another PC elsewhere with Windows 95. ] 2) My background -- Experienced programmer. I have also installed all kinds of software in the past. 3) I am installing everything in D:\HUGS98. Curreently, I have in it the following: hugs98-Dec2001.msi; hugs98-Dec2001.zip; GraphicsLib.msi; SOE.msi; win32exes.zip ------------------------------------------------------- 4) I try to do the setup by double-clicking on hugs98-Dec2001.msi. The Setup process starts off as expected.t After the first few steps, I get the message: "The Installer was interrupted before Hugs98 � December 2001 could be installed. You need to restart the installer to try again." I have tried this a few trimes, The same problem. NO CLUE TO WHAT IS MISSING OR WRONG> WHY IS THIS OCCURRING ? HOW CAN I GET AROUND IT ? The setup must be the key step. ================================= 5) If I try to run hugs.exe or winhugs.exe, it comes up with the expected Hugs Screen, with an Error Message: " Prelude not found on current path: "{Hugs}\lib;{Hugs\lib\hugs; {Hugs\lib\exts; ;{Hugs\lib\win32 FATAL ERROR: Unable to load prelude This tells me that a successful setup would have installed the lib and subdirectories in the paths above, and the executable it would have found the prelude. Is the Setup process looking for something in some default location ? This happens in some kinds of software. Could you please tell me soon what I need to do to get the setup to go through correctly ? [ Also, Could you please explain: WHAT IS the "Prelude" ? ] I am keen on getting working on Haskell, using Hugs, I would greatly appreciate your reply as soon as possible. Thank you. K. Raman ramank0(a)yahoo.com P.S. Is there a telephone number at which I can call you, if need be ? If so, during what hours ? --------------------------------- Do You Yahoo!? Yahoo! Health - Feel better, live better

2 1

Problems...
by Pedro L. P. Dias 25 Jul '02

25 Jul '02

Dear Sir: I installed Hugs in my computer, and I'm reading "A Gentle Introduction to Haskell 98" downloaded from Haskell website. I start Hugs, and, at the line command "prelude>", when I digit, for example, "add x y = x + y", an error message appear: "...unexpected '='". Also, when I digit (other example) "inc n = n + 1", the error message is "undefined variable inc", or, sometimes, for the same digited line command, "undefined variable n". I'm just typing what is showed in that manual... Could you, please, help me? Thank you very much. Best regards, Pedro. Rio de Janeiro, Brazil.

2 1

hierarchical libraries
by Ross Paterson 25 Jul '02

25 Jul '02

I've hacked up an experimental arrangement to make most of the hierarchical libraries distributed with GHC work with Hugs too. The aim is to provide source-level compatibility with both GHC 5.04 and current Hugs. The main omission is modules related to the FFI, as well as various GHC-specific stuff. People accustomed to building Hugs from CVS may wish to try it out. See docs/libraries-notes.txt for more -- you'll need to get libraries and hslibs from CVS too.

1 0

power cables
by sales 25 Jul '02

25 Jul '02

Dear Sir or Madam, It's an honor to know your company through the website. We are a large manufacturer of which specialize in manufacturing and exporting all kinds of power cords, plugs, cordsets, extension cords, sockets, and so on. Now we are planning to incorporate our business activities in your market, and we will be much obliged for your introduction to a most reliable importer handling this field. We've exported a large quantity of power cords to many countries, and enjoying a high reputation through excellent quality and price. We believe you have a great demand of power cords, please don't hesitate to contact us if you are interested in. Please advise us the following: 1) Cable specification: VDE approved H05VV-F, H03VV-F, H03VVH2-F, H05RN-F,…UL approved SJT, SJTW, HPN 18AWG, 16AWG, with USA plug. 2) Length, Color, requirement of the end. 3) Which types about plug? 4) Quantity per order? Please send us the drawings for these items so that we can quote you the best offer immediately. Please transfer this letter to Purchasing Department of your company when you received it. Your kind attention to this matter will be much appreciated. With thanks and best regards, Shanghai Foundoor Electrical Co., Ltd. Steven Xu Contact information: Shanghai Foundoor Electrical Co., Ltd. Office Address: RM 204, No. 54, Lane 250, Zhenjin Road, Shanghai, China 200333 Tel: 86-21-56348070 Fax: 86-21-56348069 E-mail: sales(a)foundoor.com http://www.foundoor.com

1 0

transitive imports
by Ross Paterson 24 Jul '02

24 Jul '02

Given these modules: module A(Stuff(Foo, Bar)) where data Stuff = Foo | Bar module B(Stuff(..)) where import A module C where import B loading C gives "INTERNAL ERROR: importEntity" Changing the import in C gives different internal errors. The particular form of the exports in A and B and the import in B seems necessary to trigger the bug.

2 2

Hugs on Linux/PPC
by Michele Campeotto 23 Jul '02

23 Jul '02

Hi, I'm trying to run Hugs on Linux/PPC, it seems to build fine but it just segfaults on startup. Is it a known problem or would you like me to send a stack trace? Cheers -- Michele - www.micampe.it "Smile, it makes people wonder what you are thinking"

1 1

expandSynFully in subst.c
by Ross Paterson 23 Jul '02

23 Jul '02

expandSynFully() is declared and defined inside #ifdef TREX but used outside of it (in getProgType).

1 0

standard input not a tty
by Ross Paterson 19 Jul '02

19 Jul '02

When hugs's standard input is not a tty, this patch stops it prompting or attempting to use readline. It also disables $$ in that situation; this could be changed if desired, but is probably the right thing. If it is put it in, the --with-readline option of configure can probably be ditched (i.e. set USE_READLINE if editline or readline is available). Index: src/input.c =================================================================== RCS file: /home/cvs/root/hugs98/src/input.c,v retrieving revision 1.43 diff -u -r1.43 input.c --- src/input.c 2002/06/14 14:41:10 1.43 +++ src/input.c 2002/07/18 15:58:05 @@ -264,6 +264,7 @@ #define SCRIPTFILE 2 /* - script file */ #define PROJFILE 3 /* - project file */ #define STRING 4 /* - string buffer? */ +#define NOKEYBOARD 5 /* - standard input, but not a tty */ static Int reading = NOTHING; @@ -322,6 +323,12 @@ hereState = START; #endif +#ifdef HAVE_ISATTY + if (!isatty(fileno(stdin))) { /* not reading from a tty: */ + reading = NOKEYBOARD; /* don't prompt or try readline */ + return; + } +#endif #if USE_READLINE /* Paranoid freeing code supplied by Sverker Nilsson (sverker(a)opq.se) * avoids accidentally freeing currentLine twice. @@ -607,6 +614,9 @@ c1 = ' '; } } + } + else if (reading==NOKEYBOARD) { + c1 = c0=='\n' ? EOF : getc(stdin); } else if (reading==STRING) { c1 = (unsigned char) *nextStringChar++;

2 1