January 2005 - Hugs-Bugs

Undefined variable bug
by John Tromp 27 Feb '07

27 Feb '07

I just found out that I can circumvent the problem by adding a line import Char to my loaded file. regards, -john

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[Hugs-bugs] Re: fromInt
by Bob Tennent 24 Jan '05

24 Jan '05

>I don't think you said anything about which version of Hugs you are using. I did in my original post: I'm using the hugs98-Nov2003-2 rpm on Linux. By "I" I mean that that's what's installed on the workstations my class is using and what some students are installing on their own computers at home. I don't think going back to a version from years ago is a realistic option. Now that I know what's going on, I can deal with it. I've suggested to Simon Thompson that he add this issue to the Errata page for his book. I don't recall this issue arising previously; shouldn't there be a Changelog to document language changes from one version of Hugs to the next? Bob T.

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Re: [Hugs-bugs] Re: fromInt
by Alwyn 24 Jan '05

24 Jan '05

On 24 Jan 2005, at 02:19, Mark P Jones wrote: > I don't think you said anything about which version of Hugs > you are using. It might be irritating, but it shouldn't be > too surprising that you will encounter problems if you try to > use a recent release with a textbook that is, if I recall > correctly, about five years old. Well, 'fromInt' figures in Mr Pope's *Tour of the Haskell Prelude*, which dates, I believe from summer 2001; mention of it seems to have been removed from the account of Numeric library in November of the same year. <http://www.haskell.org/definition/haskell98-bugs.html> I find no evidence from the original Haskell 98 Report that 'fromInt' was ever part of the public interface, so this in fact appears to amount to a minor tidying up. Thompson's book is from 1998, before the report was published. If the author does indeed make use of this function in the book, perhaps this should be submitted to him as 'errata'. Alwyn

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[Hugs-bugs] Re: fromInt
by Bob Tennent 23 Jan '05

23 Jan '05

> >| If I enter fromInt 5 at the hugs prompt, I get 5. If I use fromInt 5 >in >a module and try to load the | module, I'm told that fromInt is >undefined, >unless I explicitly import Hugs.Prelude. > > >Same with toInt, fromDouble. Evidently a mismatch between the exports of > >Hugs.Prelude and the imports of Prelude.hs. >These are internal functions of the Hugs implementation of the Prelude, >and not part of standard Haskell. It's a bug that they're visible when >no module is loaded. (The names in scope are always those in scope >inside the current module, and in this case that's the Prelude.) Then it's very unfortunate that a standard textbook such as Thompson uses fromInt and doesn't even mention fromIntegral, which I presume is the politically correct alternative.

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[Hugs-bugs] Help building on Mac OS X
by Adam 23 Jan '05

23 Jan '05

Hi there, any help as to what's going wrong for me would be greatly appreciated... I'm trying to build hugs on Mac OS X 10.3.7. The configure script runs ok, then when I do 'make' I get the following: ~/Desktop/hugs98-Nov2003/src $ make gcc -c -g -O2 hugs.c gcc -c -g -O2 edit.c gcc -c -g -O2 observe.c gcc -c -g -O2 builtin.c gcc -c -g compiler.c gcc -c -g -O2 errors.c gcc -c -g -O2 evaluator.c gcc -c -g -O2 ffi.c gcc -c -g -O2 goal.c gcc -c -g -O2 input.c gcc -c -g -O2 machdep.c /usr/include/dlfcn.h:35: warning: #warning "You are using dlopen(), a legacy API. Please use the Mach- O dylib loading APIs if at all possible" gcc -c -g -O2 machine.c machine.c:1649: illegal expression, found `&&' machine.c:1649: illegal expression, found `&&' machine.c:1649: illegal expression, found `&&' machine.c:1649: illegal expression, found `&&' machine.c:1649: illegal expression, found `&&' machine.c:1649: illegal expression, found `&&' machine.c:1649: illegal expression, found `&&' machine.c:1649: illegal expression, found `&&' machine.c:1649: illegal expression, found `&&' machine.c:1649: illegal expression, found `&&' machine.c:1649: illegal expression, found `&&' machine.c:1649: illegal expression, found `&&' machine.c:1649: illegal expression, found `&&' machine.c:1649: illegal expression, found `&&' machine.c:1649: illegal expression, found `&&' machine.c:1649: illegal expression, found `&&' machine.c:1649: illegal expression, found `&&' machine.c:1649: illegal expression, found `&&' machine.c:1649: illegal expression, found `&&' machine.c:1649: illegal expression, found `&&' machine.c:1649: illegal expression, found `&&' machine.c:1649: illegal expression, found `&&' machine.c:1649: illegal expression, found `&&' machine.c:1673: illegal statement, missing `identifier' after `goto' machine.c:1673: syntax error, missing `;' after `*' machine.c:1677: illegal statement, missing `identifier' after `goto' machine.c:1677: syntax error, missing `;' after `*' machine.c:1681: illegal statement, missing `identifier' after `goto' machine.c:1681: syntax error, missing `;' after `*' machine.c:1685: illegal statement, missing `identifier' after `goto' machine.c:1685: syntax error, missing `;' after `*' machine.c:1689: illegal statement, missing `identifier' after `goto' machine.c:1689: syntax error, missing `;' after `*' machine.c:1694: illegal statement, missing `identifier' after `goto' machine.c:1694: syntax error, missing `;' after `*' machine.c:1698: illegal statement, missing `identifier' after `goto' machine.c:1698: syntax error, missing `;' after `*' machine.c:1707: illegal statement, missing `identifier' after `goto' machine.c:1707: syntax error, missing `;' after `*' machine.c:1715: illegal statement, missing `identifier' after `goto' machine.c:1715: syntax error, missing `;' after `*' machine.c:1729: illegal statement, missing `identifier' after `goto' machine.c:1729: syntax error, missing `;' after `*' machine.c:1738: illegal statement, missing `identifier' after `goto' machine.c:1738: syntax error, missing `;' after `*' machine.c:1742: illegal statement, missing `identifier' after `goto' machine.c:1742: syntax error, missing `;' after `*' machine.c:1748: illegal statement, missing `identifier' after `goto' machine.c:1748: syntax error, missing `;' after `*' machine.c:1756: illegal statement, missing `identifier' after `goto' machine.c:1756: syntax error, missing `;' after `*' machine.c:1759: illegal statement, missing `identifier' after `goto' machine.c:1759: syntax error, missing `;' after `*' machine.c:1763: illegal statement, missing `identifier' after `goto' machine.c:1763: syntax error, missing `;' after `*' machine.c:1771: illegal statement, missing `identifier' after `goto' machine.c:1771: syntax error, missing `;' after `*' machine.c:1791: illegal statement, missing `identifier' after `goto' machine.c:1791: syntax error, missing `;' after `*' machine.c:1814: illegal statement, missing `identifier' after `goto' machine.c:1814: syntax error, missing `;' after `*' cpp-precomp: warning: errors during smart preprocessing, retrying in basic mode gcc -c -g module.c gcc -c -g -O2 opts.c gcc -c -g -O2 output.c gcc -c -g -O2 plugin.c gcc -c -g -O2 script.c gcc -c -g static.c gcc -c -g -O2 storage.c gcc -c -g -O2 strutil.c gcc -c -g subst.c gcc -c -g type.c gcc hugs.o edit.o observe.o builtin.o compiler.o errors.o evaluator.o ffi.o goal.o input.o machdep.o machine.o module.o opts.o output.o plugin.o script.o static.o storage.o strutil.o subst.o type.o version.o -lncurses -o hugs /usr/bin/ld: Undefined symbols: _doubleFromParts _part1Double _part2Double make: *** [hugs] Error 1 Many thanks, Adam

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[Hugs-bugs] Re: fromInt
by Bob Tennent 22 Jan '05

22 Jan '05

>| If I enter fromInt 5 at the hugs prompt, I get 5. If I use fromInt 5 in >a module and try to load the | module, I'm told that fromInt is undefined, >unless I explicitly import Hugs.Prelude. Same with toInt, fromDouble. Evidently a mismatch between the exports of Hugs.Prelude and the imports of Prelude.hs.

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[Hugs-bugs] fromInt
by Bob Tennent 21 Jan '05

21 Jan '05

I'm using the hugs98-Nov2003-2 rpm on Linux. If I enter fromInt 5 at the hugs prompt, I get 5. If I use fromInt 5 in a module and try to load the module, I'm told that fromInt is undefined, unless I explicitly import Hugs.Prelude. Is this a bug or a feature?

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[Hugs-bugs] Bug evaluating boolean expresion
by Pepe Gallardo 13 Jan '05

13 Jan '05

After loading the following script, b = b' && True b' = (if True then f else odd) 1 f _ = True I get the following session: || || || || || || ||__ Hugs 98: Based on the Haskell 98 standard ||___|| ||__|| ||__|| __|| Copyright (c) 1994-2003 ||---|| ___|| World Wide Web: http://haskell.org/hugs || || Report bugs to: hugs-bugs(a)haskell.org || || Version: November 2003 _______________________________________________ Haskell 98 mode: Restart with command line option -98 to enable extensions Reading file "c:\program files\hugs98\libraries\Hugs\Prelude.hs": Reading file "c:\program files\hugs98\libraries\Prelude.hs": Reading file "C:\Documents and Settings\pepe gallardo\Desktop\pepe.hs": Hugs session for: c:\program files\hugs98\libraries\Hugs\Prelude.hs c:\program files\hugs98\libraries\Prelude.hs C:\Documents and Settings\pepe gallardo\Desktop\pepe.hs Type :? for help Main> b False :: Bool Main> b' Program error: pattern match failure: instShow_v89_v1324 0 b' Regards, Pepe Gallardo

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