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I want to hear from you today my good friend.
by Farnades Clark 02 May '03

02 May '03

Mr. Farnades Clark Amsterdam, The Netherlands Dear Sir, I am an accountant and a member of the Contract Tender Board (CTB) of the Petroleum, Oil & Gas Corporation of South Africa (Pty) Ltd also known as PetroSA. I am presently on a special diplomatic duty in the South Africa foreign office in Amsterdam, the Netherlands. I got your contact through discreet inquiries in my search for a reliable individual or company who can handle a strictly confidential transaction that involves the transfer of a reasonable sum of money to a foreign account. I have no doubt in your ability to handle a financial business of considerable amount, which will form the bedrock of an extensive business partnership in due course. In unfolding this proposal, I want to count on your status that you will handle this transaction with all maturity and confidentiality it deserves. The money we want to transfer to you amount to a total of US$15.500,000.00 (Fifteen Million, Five Hundred Thousand United States Dollars) only. It was extracted from various over-invoiced contracts, masterminded by myself and some of my colleagues for our mutual benefit when the contracts was awarded by the Contracts Tender Board (CTB) of the Petroleum, Oil & Gas Corporation of South Africa (PTY) Ltd. The above over-invoiced sum has been drafted and short-listed for final payment to a foreign bank account and it has been reflected as an amount to be paid to a foreign contractor for contract that has been executed for the Petroleum, Oil & Gas Corporation of South Africa (PTY) Ltd. The money is currently floating in the suspense account of the South Africa Reserve Bank (SARB) awaiting claim by a foreign partner, which status we absolutely want you to assume. The code of conduct bureau in South Africa has made it an offence for civil servants like us to(A) operate a foreign account (B) own a foreign company and (C) take up contract while still in active service. This is why we need your assistance. Now is the optimum period to realize this fund following the recent directive given to all-federal parastatals and corporations to pay off all foreign debts. I therefore seek your assistance to allow the remittance of this fund to be made to your personal or companys bank account. We have agreed that 30% of the total sum will be given to you and 70% will be for me and my colleagues after the successful transference of the fund to your bank account. I want to assure you that all modalities for the successful transfer of this money to your account has been perfectly worked out and as such, there is no fear of failure. However, I would want to believe that you are honest enough and will not raise any misgiving attitude In any aspect of the transaction. Most importantly, you will keep this transaction very confidential so as not to tarnish the confidence reposed on these officials by the nations financial house. If this business proposal interest you, kindly indicate your willingness to me strictly on email Address: farnades_2003(a)rediffmail.com) and telephone No: +31-630-298-657 for immediate commencement of the transaction. To enable this fund to be successfully transferred to your account, you will also have to provide the following information: 1.Your company name and address that you wish to use as the beneficiary to claim the fund. 2.Your private telephone,fax Numbers. 3.Your Bank name, address and account number where you would want the money remitted. More information about the remittance of the fund to your account will be sent to you when I receive your response. Meanwhile, your swift response will help us to meet the ultimatum given to all foreign contractors in this payment quarter to ensure that funds are claimed. We also wish to discuss investment strategy with you. We have the plan of investing part of our fund in real estate with your assistance in your country. Please, treat this information as confidential. Yours faithfully, farnades clark

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(no subject)
by Thomas F. Kochmann 01 May '03

01 May '03

Hi, Does anybody know how to transfer arguments such as through C's args and argv[]? Thomas

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Fast Mutable arrays and a general question about IO
by Ron de Bruijn 01 May '03

01 May '03

Hi there, I have been busy for a couple of days now, to just get a bit more feeling on Haskell and I have read a bunch of tutorials, also about Monads and experimented of course. And now I want to use it for my real world problem. I think I understand the languageprinciples good enough, but I yet don't understand the syntax of all of the functioninterfaces. And that's my problem. I want to create the fastest array as possible in Haskell and I understood that I should use this function(the function below that creates a mutable array). The only problem is that I don't kwow how to use it. Constructing mutable arrays newArray :: (MArray a e m, Ix i) => (i, i) -> e -> m (a i e) Builds a new array, with every element initialised to undefined. Reading and writing mutable arrays readArray :: (MArray a e m, Ix i) => a i e -> i -> m e Read an element from a mutable array writeArray :: (MArray a e m, Ix i) => a i e -> i -> e -> m () Write an element in a mutable array I see it takes two arguments: a tuple of an index type(I use Int, so for example (0,1) 0 for the lower bound, 1 for the upper bound.) , but the e (according to "GHC documentation" it says the "element type"). Well the type of my elements should be my own datatype myDataType, but I can't even get it done to create simple mutable array's of Int or Bool. How can I make it work with my own datatype myDataType(could you give some examples for the use of the below functions?)? Is it OK to say that in Haskell any value that is put from an extern source of the program(reading a file, reading stdin etc.) to a really pure function, must be in a do notation(essentially being a Monadic operation)? So to put it more concrete: In any Haskell program that does IO there is always some function that has this form: do x<-someSource putBoundVariableToSomeOtherFunctionThatDoesMonadicOperations(restOfPureFunctionalProgramForExample x) So it's not possible to write some function that does the following: f::Int f do x<-getChar --suppose the Char is a number someSpecialReturnFunction x and than the result of the IO is only Int after some alterations of above code. P.S. Will it give any significant loss in speed if myDataType is lazy (no use of the !-sign in the constructors))? P.P.S. If there are array's that are even faster in Haskell, please let me know? Thanks in advance, Ron __________________________________ Do you Yahoo!? The New Yahoo! Search - Faster. Easier. Bingo. http://search.yahoo.com

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us
by eirJulie＠email.com 01 May '03

01 May '03

http://www.hoop-land.com Hello, This is that website I was telling you about where I got a 5% 30 year fixed. It is amazing, lenders try and compete for your business. Here it is! http://www.hoop-land.com Thanks, Bill Murphy Remove: http://www.hoop-land.com/rm.html

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L
by e1rJulie＠email.com 30 Apr '03

30 Apr '03

http://www.hoop-land.com Hello, This is that website I was telling you about where I got a 5% 30 year fixed. It is amazing, lenders try and compete for your business. Here it is! http://www.hoop-land.com Thanks, Bill Murphy Remove: http://www.hoop-land.com/rm.html

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Is Haskell usefull for me?
by Ron de Bruijn 29 Apr '03

29 Apr '03

Hi there, I have developed a new timetablingalgorithm, at least I think it is.. I already tested it in C++, but it's not quite complete and before it's a really great application the program will be tens of times bigger. I used Helium(subsetlanguage of Haskell) in the past few months and I think it's working better dan C++(especially because there's a lot to know about C++, before you really "know" C++). I want to use Haskell for creating a GUI. Furtermore I need some speed(code can't be more than 1.5 times slower than C++). And I want to use large array's(>60000 elements) where each element had an type in it with another 5 elements. data Thing=ConFunction Int Int Int Int Int Thus an array of Thing. I use Windows 98 Se (It seems that some libs. are only for UNIX.) Is it usefull for me to use Haskell, are there enough libraries so I can easily recreate and improve my program? Could you give some examples of possible functions or libraries I should use? Regards, Ron __________________________________ Do you Yahoo!? The New Yahoo! Search - Faster. Easier. Bingo. http://search.yahoo.com

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Re: seeking lore of the QuickCheck masters
by Lauri Alanko 29 Apr '03

29 Apr '03

On Tue, Apr 15, 2003 at 11:40:25AM +0100, Malcolm Wallace wrote: > You want a generator that can produce an arbitrary code fragment, > *given* what type you want it to have. So first, generate an arbitrary > type, then generate an arbitrary expression for it. "Generate an arbitrary proposition, then generate an arbitrary proof for it." Boy, it's _that_ simple? :) Lauri Alanko la(a)iki.fi

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Online judge and Haskell?
by Steffen Mazanek 28 Apr '03

28 Apr '03

Hello, it's me again and I have a new mad idea. There are a lot of programming contests out there and unfortunately most (all?) of them do not allow Haskell code till now! I think, this is hard to accept. Why not ask the people which run acm.uva.es/problemset to provide their problem sets, input and output files and the basic judging software and install it at haskell.org? Alternatively this may be a nice project for a student. I think an adaption of this software to permit Haskell code can not be that difficult! Do you think there is a need for such a project? Maybe it could help Haskell to become a part of official programming contests and hence to gain more popularity. I'm sorry to say, that due to another project my free time is very limited so I can not get it going by only myself. Ciao, Steffen -- Haskell: that's where I just curry until fail, unwords any error, drop all undefined, maybe break, otherwise in sequence span isControl and take max $, id: (d:[])

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mmap and IArray slices
by David Roundy 28 Apr '03

28 Apr '03

I had a couple ideas, and I was wondering if they were good ones. One is the idea of a slice function on an IArray: a' = slice a (i,j) giving an array with the elements i..j of array a. The nifty idea would be that this could be done without any memory copy. The catch, of course, would be that you might end up having to retain the entire array a just because you need a little slice of it. However, I think this risk (which should be documented) would be overwhelmed by the increased efficiency (both in space and time) gains that would be possible. The most obvious (to me at least, since I've been working a lot with PackedStrings recently) application would be in substrPS. Using slice, this would be an O(1) operation, rather than an O(n) operation, and would use essentially no memory (at the cost of retaining the mother string). I'm thinking that it may even be possible to make the GC smart enough to get rid of mother strings which are needed by very few children (at least if it's desperate), if array slices were supported at a low enough level... I imagine they'd have to be supported at a very low level. The second (and related) idea is that it would be nice to be able to use mmap on a readonly file to read it into an immutable array. Of course, this works really nicely with array slices, since with the slices the mmapped array wouldn't need to be copied, and could remain backed by the file itself. I imagine being able to read a 100M file into a PackedString, then run linesPS (or possibly a special slice version of linesPS) on it, and have a [PackedString], all of which is backed by the file, so when memory gets tight it can be just thrown away (by the VM system) and then get read in again when I use it. The mmap idea seems even tougher than the slice idea, as it would require (preferably) keeping track of all mmapped regions so when the file is closed they could all be copied over into normal memory and unmapped. Technically they could remain mmapped after the file is closed, but I think that would cause problems if the program then wants to reopen the file for writing. Anyhow, those are just a couple of ideas I had, and I have nowhere near the knowledge if haskell internals to tell if they are workable or not. -- David Roundy http://www.abridgegame.org

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RE: Is this a bug in multithreading code?
by Simon Marlow 28 Apr '03

28 Apr '03

> Nick Name <nick.name(a)inwind.it> > > You are right, [...] > > I further conjecture that more than half of all space leaks can be > identified not by profiling your code but by running the following > command: > > grep '+1' *.hs *.lhs > > I'm half joking but I've found that this one is very common in certain > kinds of code. Good idea! Here's another space-leak-avoiding trick: whenever you write Int as a constructor field, consider writing !Int instead. Same goes for other basic types and tuples. This pre-emptive space leak avoidance helps us in GHC quite a bit. Cheers, Simon

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