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ASSISTANCE NEEDED.
by DR DAN MOMOH 15 Apr '02

15 Apr '02

DR DAN MOMOH FED.MINISTRY OF PETROLUEM REOURCES(F.M.P.R) LAGOS NIGERIA. ATTN:SIR, REQUEST FOR ASSISTANCE- STRICTLY CONFIDENTIAL I amDR. DAN MOMOH, an accountant in the Ministry of petroleum Resources (MPR) and a member of a seven-man Tender Board in charge of contract review and payment approvals. I came to know of you in my search for a reliable person to handle a very confidential transaction that involves the transfer of a huge sum of money to a foreign account. It may sound strange but exercise patience and read on. There were series of contracts executed by a Consortium Multinational in the Oil industry in favor of Ministry of Petroleum Resources among which were: 1. The extension of pipeline network within Nigeria for crude oil, Down stream products distribution and subsequent evacuation- US$ 195 Million. 2. Contract for the Turn Around Maintenance (TAM) of the various refineries in the country~ US$ 152 Million. 3. The construction of storage tanks for petroleum products (Depots)~ US$240 Million. The original values of this contract were deliberately over invoiced to the sum of US $35.5million American Dollars which has now been approved and is now ready to be transferred being that the companies that actually executed these contracts has been fully paid and project officially commissioned. Consequently, my colleagues and I are willing to transfer the total amount to your account for subsequent disbursement since we are Civil Servant and are prohibited by the Code of Conduct Bureau ( Civil Servant Laws) from opening/ operating foreign account in our names. Needless to say, the trust posed on you at this juncture is enormous. In return, we have agreed to offer you 20% of the transferred sum while 10% shall be set aside for accidental expenses (Internal & External) between the parties in the course of the transfer. We will mandate you to draw up an investment plan for us of which you will control since we cannot bring our shares back to Nigeria. We are very interested in investing in real estate in your country. You must however note that this transaction is subjected to the following terms and conditions: 1. Our conviction of your transparent honesty and diligence. 2. That you would treat this transaction with utmost secrecy and confidentiality because of the circumstances we now find ourselves. 3. That the funds would be transferred to an account over which you have absolute control. Modalities have been worked out at the highest level of the presidency at the Central Bank of Nigeria for the immediate transfer of the funds within 14 working days, subject to your satisfaction of the above stated terms. Our assurance is that your role is 100% risk free. To accord this transaction, the legality it deserves and for mutual security of the parties involved and the funds, the whole approval procedures will be officially and legally processed with your name or the name of your company you may nominate as the bonafide beneficiary. Also, be informed that our main reason of contacting you is for the obvious reason that we will want to invest these funds in the real estate. It is our believe that you can be of immense help in this regards. Kindly expedite action so as to enable us include this transaction into this batch as payment to foreign contractors is usually carried out on quarterly basis. Please, contact me as soon as possible on my private e-mail address:almoore@hotvoice.com Best regards, DR. DAN MOMOH

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Re: ASSISTANCE NEEDED.
by Brian Tawney 15 Apr '02

15 Apr '02

>REQUEST FOR ASSISTANCE- STRICTLY CONFIDENTIAL This is a common scam. Everyone should ignore it and move on. If you're interested, here's a URL to a site about this particular con-game: http://www.egnet.co.uk/nigeria/index.asp _________________________________________________________________ Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp.

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Re: Help need "Cannot use type synonym in instance head"
by Jon Cast 14 Apr '02

14 Apr '02

Please keep this on the list, so everyone can benefit. Benny <neon_2001(a)hotmail.com> wrote: > Hello Jon > Thanks for the help. But it still didn't work after I changed the > codes from: > > type Poly = [Float] > > addPoly::Poly->Poly->Poly > > addPoly x y = zipWith (+) x y > > instance (Float a) => Num (Poly a) where > > (+) = addPoly > to your suggestion: > type Poly = [Float] > addPoly::Poly->Poly->Poly > addPoly x y = zipWith (+) x y > instance Num [Float] where > (+) = addPoly > I received this erreor message "Syntax error in instance head > (variable expected)". I sent this suggestion without actually trying it; unfortunately, as you discovered, it violates the rules of the Haskell 98 language. Please disregard this suggestion. > Then I tried your second suggestion, so I changed to codes to: > type Poly = [Float] > newtype Poly = Poly [Float] > addPoly::Poly->Poly->Poly > addPoly (Poly x) (Poly y) = Poly (zipWith (+) x y) > instance (Float a) => Num (Poly a) where > (+) = addPoly > Then I received this error message " Repeated definition of type > constructor "Poly"". What I meant was the following: > newtype Poly = Poly [Float] > addPoly::Poly->Poly->Poly > addPoly (Poly x) (Poly y) = Poly (zipWith (+) x y) > instance Num Poly where > (+) = addPoly I.e., delete the type declaration as well as the extraneous information from the instance. <snip> Btw., you'll also want instances of Eq and Show to get Num to go through. > Thank you very much You're welcome > Cheers > Benny Jon Cast

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Help need "Cannot use type synonym in instance head"
by Benny 14 Apr '02

14 Apr '02

type Poly = [Float] addPoly::Poly->Poly->Poly addPoly x y = zipWith (+) x y instance (Float a) => Num (Poly a) where (+) = addPoly I got the error message "Cannot use type synonym in instance head" when I was trying to compile the codes above. Can anyone tell me why and how to solve it? Cheers Benny

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Re: Help need "Cannot use type synonym in instance head"
by Ashley Yakeley 14 Apr '02

14 Apr '02

At 2002-04-13 21:22, Benny wrote: >type Poly = [Float] > >addPoly::Poly->Poly->Poly >addPoly x y = zipWith (+) x y > >instance (Float a) => Num (Poly a) where > (+) = addPoly > > >I got the error message "Cannot use type synonym in instance head" when I >was trying to compile the codes above. Can anyone tell me why and how to >solve it? There are at least two errors here. Firstly the context of your instance "(Float a) =>" is wrong. "Float" is not a class. Secondly, "(Poly a)" is meaningless, since Poly is a type and does not take any parameter. -- Ashley Yakeley, Seattle WA

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Theorems for free.
by Long Goodbye 13 Apr '02

13 Apr '02

I have heard that Philip Wadlers article "Theorems for free" has been written in a "CT terms" version in addition to the one that can be found at Nec. If this is the case then I would very much like to have a pointer to where this file can be found. Thank you, Henrik Ljung _________________________________________________________________ Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp.

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writeFile and buffering
by Jorge Adriano 13 Apr '02

13 Apr '02

Hi, Is there any way to use writeFile with no buffering? I know that with handles I can do, > hSetBuffering hdl NoBuffering Since all I do is write a string to a file, I don't see much need for handles here though. I wanted no buffer to be able to check the status of the program by accessing the file - I calculate thousands of values, but just write few hundred so it usually ends up just writing the string in the very end. Thanks in advance J.A.

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Re: Bug in IO libraries when sending data through a pipe?
by Manuel M. T. Chakravarty 13 Apr '02

13 Apr '02

Jens Petersen <juhp(a)01.246.ne.jp> wrote, > Jens Petersen <petersen(a)redhat.com> writes: > > Also I just rediscovered Manuel Chakravarty's HPL (Haskell > Ports Library), which provides a rather elegant, > sophisticated approach. > > http://www.cse.unsw.edu.au/~chak/haskell/ports/ > > It compiles fine under ghc-5.02.2, and using the BufferMode > patch included at the end output seems to be ok, Why LineBuffering? Doesn't really change anything for me (same GHC version). > but input > of more than 2048 bytes doesn't seem to be being handled > reliably. [..] > mostly gives no output, but occasionally I see > > Warning: Ports.listenToPort: Attempted to listen to a closed port! > > Needs some debugging I guess. :) I guess, it needs more documentation. Your test program is wrong in two places. The function `listenToPort' starts to listens at the given port exactly when `listenToPort' is executed; ie, any data that goes over the port earlier will not be received in the stream that this call to `listenToPort' returns. You wrote > outpt <- newPort ' ' > errpt <- newPort ' ' > let p = proc cmd args > p inpt outpt errpt > putStrLn "output:" > out <- listenToPort outpt As the processes `cmd' is fork()ed in a separate thread, it may already have finshed its business until you get to `listenToPort outpt', which means you have missed all the data. For similar reasons > errclosed <- isClosedPort errpt > unless errclosed $ > do > err <- listenToPort errpt isn't recommended. I changed your program to what I have appended. It then works for me for the % cat 4096 | test-processes cat test...except that I sometimes get a "Broken Pipe". So, I guess, I have to do some debugging after all (plus improve the documentation). Cheers, Manuel PS: I'll add your program to the ports/tests/ directory if you don't mind. -=- module Main where import Processes import Ports import IO (openFile, hGetContents, IOMode(..), hSetBuffering, BufferMode(..)) import Monad (unless) main :: IO() main = do inpt <- getContents withPorts [] $ \ (cmd:args) -> do outpt <- newPort ' ' errpt <- newPort ' ' out <- listenToPort outpt err <- listenToPort errpt let p = proc cmd args p inpt outpt errpt putStrLn "output:" mapM_ putStrLn $ lines out putStrLn "error:" putStr err putStrLn "test finished"

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recursive function
by excellent2002 10 Apr '02

10 Apr '02

Hi,I want to write a recursive function to change list as this form ["whantever","\n","it is","\n","I","don;t","care"] to ["whatever","it is","I \n don't \n care"], but I failed to work it out. Anybody can help me ? Thank you very much If there is no "\n",between the strings, add "\n" beteen them and merge these string. Regards Alan ----------------------------------------- ÒÚÌÆÉú»îÆ·ÅÆµÚÒ»Ö÷Žò http://bag.etang.com/payment_1.htm ÒÚÌÆ¶ÌÐÅ£¬ÄúÌùÉíµÄÊ±ÉÐ¹ËÎÊ http://sms.etang.com Ã¿ÌìÈÃÄãÇáËÉŒÇµ¥ŽÊ http://www.etang.com/texthanburg/index.htm ÃÀ¹úŽóÑ§Ö®ÃÅÎªÄã¶ø¿ª °Ù·Ö°ÙÄÃœ±Ñ§œð http://campus.etang.com/html/academic/usa/scho/scho017.htm

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subscribe
by Leif Eriksen 09 Apr '02

09 Apr '02

Leif Eriksen Software Engineer AusRegistry Pty Ltd Level 12, 10 Queens Rd. Melbourne, Victoria. Australia 3004. Ph: +61 3 9866 1990 Fax: +61 3 9866 1970 Email: leif(a)ausregistry.com.au Web: www.ausregistry.com.au Registrars: www.ausregistry.net.au

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