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Today's Topics:
1. Re: Problems with ghc (Daniel Fischer)
2. Re: Problems with ghc (Paul Johnston)
3. Re: Problems with ghc (Paul Johnston)
4. Re: Problems with ghc (Daniel Fischer)
5. better way to create Array defined on all indices (Larry Evans)
6. fix (Matthew J. Williams)
7. Re: fix (Brandon S. Allbery KF8NH)
8. Re: fix (Brandon S. Allbery KF8NH)
9. Re: better way to create Array defined on all indices
(Larry Evans)
----------------------------------------------------------------------
Message: 1
Date: Wed, 15 Oct 2008 15:32:26 +0200
From: Daniel Fischer <[EMAIL PROTECTED]>
Subject: Re: [Haskell-beginners] Problems with ghc
To: beginners@haskell.org
Message-ID: <[EMAIL PROTECTED]>
Content-Type: text/plain; charset="iso-8859-1"
Am Mittwoch, 15. Oktober 2008 14:51 schrieb Paul Johnston:
> Many thanks but no joy see below
> Think it could be gmp which I had to also compile but it passed all its
> checks.
Seems the linker can't find gmp.
Try compiling with the -L/path/to/gmp option (if that works, we at least have
identified the problem, of course, for a real fix you would have to include
that directory to the linker's search path).
> Regards Paul
Cheers,
Daniel
------------------------------
Message: 2
Date: Wed, 15 Oct 2008 14:36:51 +0100
From: Paul Johnston <[EMAIL PROTECTED]>
Subject: Re: [Haskell-beginners] Problems with ghc
To: Daniel Fischer <[EMAIL PROTECTED]>
Cc: beginners@haskell.org
Message-ID: <[EMAIL PROTECTED]>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Daniel Fischer wrote:
> Am Mittwoch, 15. Oktober 2008 14:51 schrieb Paul Johnston:
>
>> Many thanks but no joy see below
>> Think it could be gmp which I had to also compile but it passed all its
>> checks.
>>
>
> Seems the linker can't find gmp.
> Try compiling with the -L/path/to/gmp option (if that works, we at least have
> identified the problem, of course, for a real fix you would have to include
> that directory to the linker's search path).
>
>
>> Regards Paul
>>
>
> Cheers,
> Daniel
> _______________________________________________
> Beginners mailing list
> Beginners@haskell.org
> http://www.haskell.org/mailman/listinfo/beginners
>
Sorted :-)
[EMAIL PROTECTED]:~/haskell/aht/3$ ghc
-L=/usr/local/lib/ -o Haq --make Haq.hs
[1 of 1] Compiling Main ( Haq.hs, Haq.o )
Linking Haq ...
[EMAIL PROTECTED]:~/haskell/aht/3$ ./Haq "Bother"
"Haq! BotherOr not!"
[EMAIL PROTECTED]:~/haskell/aht/3$
Tried putting /usr/local/lib in $LD_LIBRARY_PATH but that didn't seem to
work, pity.
Anyway many, many thanks
Paul
------------------------------
Message: 3
Date: Wed, 15 Oct 2008 15:35:03 +0100
From: Paul Johnston <[EMAIL PROTECTED]>
Subject: [Haskell-beginners] Re: Problems with ghc
To: Christian Maeder <[EMAIL PROTECTED]>
Cc: beginners@haskell.org
Message-ID: <[EMAIL PROTECTED]>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Christian Maeder wrote:
> Paul Johnston wrote:
>
>> [EMAIL PROTECTED]:~/haskell/aht/3$ ghc
>> -L=/usr/local/lib/ -o Haq --make Haq.hs
>> [1 of 1] Compiling Main ( Haq.hs, Haq.o )
>> Linking Haq ...
>> [EMAIL PROTECTED]:~/haskell/aht/3$ ./Haq "Bother"
>> "Haq! BotherOr not!"
>> [EMAIL PROTECTED]:~/haskell/aht/3$
>>
>> Tried putting /usr/local/lib in $LD_LIBRARY_PATH but that didn't seem to
>> work, pity.
>> Anyway many, many thanks
>>
>
> I think setting LIBRARY_PATH would work.
>
> Cheers Christian
>
Tried setting both LD_LIBRARY_PATH and LIBRARY_PATH
[EMAIL PROTECTED]:~/haskell/aht/3$ env | grep LIBRARY
LIBRARY_PATH=/usr/lib:/opt/csw/lib:/opt/csw/lib/engines:/usr/local/lib
LD_LIBRARY_PATH=/usr/lib:/opt/csw/lib:/opt/csw/lib/engines:/usr/local/lib
[EMAIL PROTECTED]:~/haskell/aht/3$
Still same issue
[EMAIL PROTECTED]:~/haskell/aht/3$ touch Haq.hs
[EMAIL PROTECTED]:~/haskell/aht/3$ ghc -o Haq Haq.hs
Undefined first referenced
symbol in file
__gmpz_tdiv_q
/usr/local/lib/ghc-6.8.3/libHSrts.a(PrimOps.o)
__gmpz_tdiv_r
/usr/local/lib/ghc-6.8.3/libHSrts.a(PrimOps.o)
__gmpn_cmp
/usr/local/lib/ghc-6.8.3/libHSrts.a(PrimOps.o)
__gmpz_add
/usr/local/lib/ghc-6.8.3/libHSrts.a(PrimOps.o)
__gmpz_and
/usr/local/lib/ghc-6.8.3/libHSrts.a(PrimOps.o)
__gmpz_gcd
/usr/local/lib/ghc-6.8.3/libHSrts.a(PrimOps.o)
__gmpz_ior
/usr/local/lib/ghc-6.8.3/libHSrts.a(PrimOps.o)
__gmpz_com
/usr/local/lib/ghc-6.8.3/libHSrts.a(PrimOps.o)
__gmpz_mul
/usr/local/lib/ghc-6.8.3/libHSrts.a(PrimOps.o)
__gmpz_xor
/usr/local/lib/ghc-6.8.3/libHSrts.a(PrimOps.o)
__gmpz_sub
/usr/local/lib/ghc-6.8.3/libHSrts.a(PrimOps.o)
__gmpn_gcd_1
/usr/local/lib/ghc-6.8.3/libHSrts.a(PrimOps.o)
__gmpz_init
/usr/local/lib/ghc-6.8.3/libHSrts.a(PrimOps.o)
__gmpz_fdiv_qr
/usr/local/lib/ghc-6.8.3/libHSrts.a(PrimOps.o)
__gmp_set_memory_functions
/usr/local/lib/ghc-6.8.3/libHSrts.a(Storage.o)
__gmpz_divexact
/usr/local/lib/ghc-6.8.3/libHSrts.a(PrimOps.o)
__gmpz_tdiv_qr
/usr/local/lib/ghc-6.8.3/libHSrts.a(PrimOps.o)
ld: fatal: Symbol referencing errors. No output written to Haq
collect2: ld returned 1 exit status
[EMAIL PROTECTED]:~/haskell/aht/3$
Cheers Paul
------------------------------
Message: 4
Date: Wed, 15 Oct 2008 17:04:13 +0200
From: Daniel Fischer <[EMAIL PROTECTED]>
Subject: [Haskell-beginners] Re: Problems with ghc
To: beginners@haskell.org
Message-ID: <[EMAIL PROTECTED]>
Content-Type: text/plain; charset="iso-8859-1"
Am Mittwoch, 15. Oktober 2008 16:35 schrieb Paul Johnston:
> Christian Maeder wrote:
> > Paul Johnston wrote:
> >> [EMAIL PROTECTED]:~/haskell/aht/3$ ghc
> >> -L=/usr/local/lib/ -o Haq --make Haq.hs
> >> [1 of 1] Compiling Main ( Haq.hs, Haq.o )
> >> Linking Haq ...
> >> [EMAIL PROTECTED]:~/haskell/aht/3$ ./Haq "Bother"
> >> "Haq! BotherOr not!"
> >> [EMAIL PROTECTED]:~/haskell/aht/3$
> >>
> >> Tried putting /usr/local/lib in $LD_LIBRARY_PATH but that didn't seem to
> >> work, pity.
> >> Anyway many, many thanks
> >
> > I think setting LIBRARY_PATH would work.
> >
> > Cheers Christian
>
> Tried setting both LD_LIBRARY_PATH and LIBRARY_PATH
>
> [EMAIL PROTECTED]:~/haskell/aht/3$ env | grep LIBRARY
> LIBRARY_PATH=/usr/lib:/opt/csw/lib:/opt/csw/lib/engines:/usr/local/lib
> LD_LIBRARY_PATH=/usr/lib:/opt/csw/lib:/opt/csw/lib/engines:/usr/local/lib
> [EMAIL PROTECTED]:~/haskell/aht/3$
>
>
> Still same issue
>
> [EMAIL PROTECTED]:~/haskell/aht/3$ touch Haq.hs
> [EMAIL PROTECTED]:~/haskell/aht/3$ ghc -o Haq Haq.hs
What happens with --make now?
>
> Cheers Paul
------------------------------
Message: 5
Date: Wed, 15 Oct 2008 16:05:30 -0500
From: Larry Evans <[EMAIL PROTECTED]>
Subject: [Haskell-beginners] better way to create Array defined on all
indices
To: beginners@haskell.org
Message-ID: <[EMAIL PROTECTED]>
Content-Type: text/plain; charset="iso-8859-1"
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------------------------------
Message: 6
Date: Wed, 15 Oct 2008 23:51:45 +0100
From: "Matthew J. Williams" <[EMAIL PROTECTED]>
Subject: [Haskell-beginners] fix
To: beginners@haskell.org
Message-ID: <[EMAIL PROTECTED]>
Content-Type: text/plain; charset="us-ascii"; format=flowed
hello listers, a few days ago A fellow lister sent me the following link:
http://en.wikibooks.org/wiki/Haskell/Fix_and_recursion
The 'fix' function is interesting to say the least. There is one
example that I've had difficulty expanding:
fix (\rec n -> if n == 0 then 1 else n * rec (n-1)) 5
120
My interpretation:
fix (\rec n -> if n == 0 then 1 else n * rec (n-1)) 5
((\rec n -> if n == 0 then 1 else n * rec (n-1)) (fix (\rec n -> if
n == 0 then 1 else n * rec (n-1)) )) 5
. . .
Yet, it does not quite explain how 'fix' does not result in infinite
recursion.
Sincerely
Matthew J. Williams
------------------------------
Message: 7
Date: Wed, 15 Oct 2008 19:04:03 -0400
From: "Brandon S. Allbery KF8NH" <[EMAIL PROTECTED]>
Subject: Re: [Haskell-beginners] fix
To: "Matthew J. Williams" <[EMAIL PROTECTED]>
Cc: beginners@haskell.org
Message-ID: <[EMAIL PROTECTED]>
Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes
On 2008 Oct 15, at 18:51, Matthew J. Williams wrote:
> fix (\rec n -> if n == 0 then 1 else n * rec (n-1)) 5
> 120
>
> My interpretation:
> fix (\rec n -> if n == 0 then 1 else n * rec (n-1)) 5
> ((\rec n -> if n == 0 then 1 else n * rec (n-1)) (fix (\rec n -> if
> n == 0 then 1 else n * rec (n-1)) )) 5
> . . .
>
> Yet, it does not quite explain how 'fix' does not result in
> infinite recursion.
Remember, Haskell is non-strict. When the computation reaches 0, the
"then" branch of the conditional is evaluated and the "else" is
unneeded and therefore ignored, so its re-invocation isn't seen.
--
brandon s. allbery [solaris,freebsd,perl,pugs,haskell] [EMAIL PROTECTED]
system administrator [openafs,heimdal,too many hats] [EMAIL PROTECTED]
electrical and computer engineering, carnegie mellon university KF8NH
------------------------------
Message: 8
Date: Wed, 15 Oct 2008 19:09:24 -0400
From: "Brandon S. Allbery KF8NH" <[EMAIL PROTECTED]>
Subject: Re: [Haskell-beginners] fix
To: "Brandon S. Allbery KF8NH" <[EMAIL PROTECTED]>
Cc: beginners@haskell.org
Message-ID: <[EMAIL PROTECTED]>
Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes
On 2008 Oct 15, at 19:04, Brandon S. Allbery KF8NH wrote:
> On 2008 Oct 15, at 18:51, Matthew J. Williams wrote:
>> Yet, it does not quite explain how 'fix' does not result in
>> infinite recursion.
>
> Remember, Haskell is non-strict. When the computation reaches 0,
> the "then" branch of the conditional is evaluated and the "else" is
> unneeded and therefore ignored, so its re-invocation isn't seen.
Think about this, btw: you can create new control operations as
ordinary functions In strict languages you need to rely on special
syntax (such as Perl's IO syntax + \& prototype, or Ruby's special
block/proc syntax; in LISP/Scheme, you have to use a macro and/or
quoting); non-strict evaluation gives it to you for free.
--
brandon s. allbery [solaris,freebsd,perl,pugs,haskell] [EMAIL PROTECTED]
system administrator [openafs,heimdal,too many hats] [EMAIL PROTECTED]
electrical and computer engineering, carnegie mellon university KF8NH
------------------------------
Message: 9
Date: Wed, 15 Oct 2008 23:50:53 -0500
From: Larry Evans <[EMAIL PROTECTED]>
Subject: Re: [Haskell-beginners] better way to create Array defined on
all indices
To: beginners@haskell.org
Message-ID: <[EMAIL PROTECTED]>
Content-Type: text/plain; charset="iso-8859-1"
On 10/15/08 16:05, Larry Evans wrote:
> I'd like to have an Array indices values
> (see http://haskell.org/onlinereport/array.html)
> defined on [minBound::indices ... maxBound::indices].
> The attached does this; however, it also allows
> duplicate definitions (e.g. in the attached, the
> value for Term index is defined twice).
>
> Is there a better way to do this? Maybe a
> way that doesn't use all the contexts?
> Also, is there a way to do it so that the value
> associated with an index is not redefined?
The aforementioned array.html has:
_ -> error "Array.!: \
\multiply defined array element")
suggesting it should detect redefinitions; however,
the library on my system apparently doesn't do that.
It will detect missing defintions with the same error
found in array.html:
[] -> error "Array.!: \
\undefined array element"
Is this a bug in my ghc library? I'n on ubuntu and
synaptic shows the ghc6 version as:
6.8.2-2ubuntu1
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