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Joe Marshall: Happy 80th Birthday to Neil Armstrong

Planet Scheme - Thu, 08/05/2010 - 18:07
Neil Armstrong turns 80 years old today!

Hey RACIST and INcompetent FBI/CIA Bustards where is the ANTHRAX MAILER ??? Where are the 4 blackboxes, where are the 5 dancing israelis and what is the status of FORENSIC evidence and trace of NANO THERMITE in WTC dust ?

comp.lang.scheme - Thu, 08/05/2010 - 14:00
Hey RACIST and INcompetent FBI/CIA Bustards where is the ANTHRAX
MAILER ??? Where are the 4 blackboxes, where are the 5 dancing
israelis and what is the status of FORENSIC evidence and trace of NANO
THERMITE in WTC dust ?
The FAT per DIEM FBI bustards use our TAX PAYER MONEY and INCOMPETENCE
is UNACCEPTABLE.

Re: Please, stop spamming

comp.lang.scheme - Thu, 08/05/2010 - 12:00
[snip]
Daniel,
This spam is by CIA, MOSSAD, AIPAC, ZIONISTS to HIDE a slight mention
of their crimes. Ignore it, and continue, if you want to success.
I agree with someone that they carried out 911 to destroy FREEDOMS.
One paradigm of these ODIOUS CRIMINALS is to blame what they do on
others and with a VIGOR to lie so it appears a truth. These BUSTARDS

The (x . y) construct

comp.lang.scheme - Thu, 08/05/2010 - 10:00
(x . y) will have to be execised from the language on the grounds of
hardware efficiency.
The problem relates to the difference between a circular reference and
a self-reference, and strategies for garbage collection using
counting.
The strong non circular list argument says that all circular
references can be emulated with self references. An removing the

Re: GNU Emacs Developement Inefficiency (commentary)

comp.lang.scheme - Thu, 08/05/2010 - 06:00
Well, there is a lot of resistance from the emacs community in sharing
information. Richard Stallman is a true STALLER of progress. He has
held the whole process hostage by not sharing information. He has
RENEGED on his promise to make it truly open by suppressing
documentation of his softwares.
The one who has the key can open the lock in a jiffy.

[ANN] Call for Participation for 2010 Workshop on Scheme and Functional Programming

comp.lang.scheme - Wed, 08/04/2010 - 17:00
CALL FOR PARTICIPATION
2010 Workshop on Scheme and Functional Programming
Montreal, Quebec, Canada
Saturday and Sunday August 21-22, 2010
[link]
*** ONLINE REGISTRATION IS NOW OPEN FOR THE WORKSHOP ***

Re: Programming games in Scheme?

comp.lang.scheme - Wed, 08/04/2010 - 05:00
There are games written in Scheme. There aren't a lot because, well,
there aren't as many people interested in writing games that are
interested in writing games in Scheme. :-)
That said, most of the more well known Scheme implementations have
OpenGL bindings, and plenty of them have 2 dimensional drawing

PLT Scheme: Racket v5.0.1

Planet Scheme - Wed, 08/04/2010 - 03:36
Racket version 5.0.1 is now available from
  http://racket-lang.org/
  • Datalog is a lightweight deductive database system with Racket integration. It is now available in the datalog collection and with #lang datalog.
  • Racklog provides Prolog-style logic programming in Racket, adapted from Dorai Sitaram's Schelog package. It is available in the racklog collection and now as #lang racklog.
  • By default make install and raco setup compile collections in parallel on all available processors. (Use raco setup -j 1 to disable, if necessary.)
  • Changes (as part of 5.0) in the racket language compared to the scheme language: constructor-style printing, a struct alternative to define-struct that fits more naturally with match and constructor-style printing, bytecode-dependency management via SHA-1 hashes instead of just timestamps (where the openssl/sha1 library provides the SHA-1 hash function), a reorganization of scheme/foreign into ffi/unsafe and associated libraries, and new printing functions eprintf and displayln. Also, a generator from racket/generator is required to have the form (generator () body ...), which supports a planned extension to let a generator accept arguments.
  • Changes to the racket language (since 5.0): internal-definition positions allow mixing expressions with definitions, full continuations can escape past a continuation barrier, custodians can attempt to terminate subprocesses and subprocess groups (see current-subprocess-custodian-mode, subprocess-group-enabled), the JIT supports additional unboxing flonum operations and unsafe variants, ffi/unsafe provides an asychronous-call mechanism to deal with foreign threads, a new "." modifier for format string directives (e.g., "~.s" and "~.a") limits the respective output to (error-print-width) characters.
  • The core type system of Typed Racket has been substantially revised. In particular, Typed Racket can now follow significantly more sophisticated reasoning about the relationships between predicates. Additionally, Typed Racket now allows variable arity types in more places, allowing programmers to specify variable-arity lists.
  • We are working on an optimizing version of Typed Racket that takes advantage of type information for certain classes of programs. This project is a work in progress. For those interested, see the documentation for #:optimized.
  • The web-server/formlets library adds a formlet* form that allows dynamic formlet construction, as opposed to formlet which requires syntactic Xexprs and static formlets. Several new library formlets are added.
  • The syntax/parse library has new support for matching literals at different phases using the #:phase argument for literals and literal sets.
  • RackUnit now includes a GUI test runner as rackunit/gui.
  • The 2htdp/image library now includes flip-vertical and flip-horizontal operations that mirror images (vertically and horizontally).

*** StudyCourse :: The Conversion of KHAZARS to Jews and thence TRANSFORMATION to ZIONIST ATHEISTS ***

comp.lang.scheme - Wed, 08/04/2010 - 03:00
Self-Study Course : The Conversion of KHAZARS to Jews and thence
TRANSFORMATION to ZIONIST ATHEISTS
First, we will present the TRANSFORMATION, using HIGHLY AUTHENTIC
source . Lying and Deception is the second nature of zionists , so we
cant contaminate ourselves with an iota of it. We present evidence

Joe Marshall: My definition

Planet Scheme - Tue, 08/03/2010 - 19:10
Here's my definition:A computer program is a description of a process which is formal enough to be carried out by a machine. Most of the other definitions describe a program as a ‘set of instructions’. Some of the definitions suggest that these instructions should be organized in some way, perhaps as a (linear) list. These instructions ‘make the computer do things’, ‘bring about a certain result’, ‘cause the computer to behave in a predetermined manner’, or ‘alter the contents of memory’. But these definitions have an explicit or implicit assumption: a sequential, imperative mode of thought.

Look at this Prolog code:
append(c(H,T), B, c(H,TB)) <= append(T, B, TB).
append(nil, B, B).
This code describes relationship of appending lists, but it doesn't specify how to accomplish the appending. Is the first clause an ‘instruction’ to build a list, or to take one apart? Are the clauses to be run in any particular order? Is there a deterministic ‘answer’?

Programming Praxis: Carl Hewitt’s Same-Fringe Problem

Planet Scheme - Tue, 08/03/2010 - 10:00

Long ago, Carl Hewitt created the same-fringe problem as a demonstration of the simplest problem that requires concurrency to implement efficiently: Given two binary trees, determine if they have the same leaves in the same order, regardless of their internal structure. A solution that simply flattens both trees into lists and compares them element-by-element is unacceptable, as it requires space to store the intermediate lists and time to compute them even if a difference arises early in the computation.

Your task is to write a function that tests if two trees have the same fringe. When you are finished, you are welcome to read or run a suggested solution, or to post your own solution or discuss the exercise in the comments below.


Joe Marshall: What is a ‘computer program’?

Planet Scheme - Mon, 08/02/2010 - 23:53
This seems like a simple enough question.

Here's what the web says. A computer program is
  1. a set of statements or instructions to be used directly or indirectly in a computer in order to bring about a certain result
  2. what makes the computer do things
  3. a set of instructions written in a programming language
  4. an algorithm written in a language that a computer can understand
  5. simply a long list of code written in another language
  6. a set of instructions for altering the contents of various words in the computer's memory
  7. a carefully thought out, step-by-step, set of instructions prepared by a programmer
  8. an organized list of instructions that, when executed, causes the computer to behave in a predetermined manner
  9. is a procedure (or algorithm) for performing some computation
  10. a bunch of instructions run by a computer, just like a storybook is just a whole bunch of sentences read by the reader

Does anyone have any better definitions?

Programming Praxis: Fibonacci Numbers

Planet Scheme - Fri, 07/30/2010 - 10:00

One of the first functions taught to programmers who are just learning about recursion is the function to compute the fibonacci numbers. The naive function takes exponential time, as each recursive call must compute the values of smaller fibonacci numbers, so programmers are next taught how to remove the recursion by explicitly storing state information, giving a linear-time iterative algorithm. The upshot is that programming students are left with the impression that recursion is bad and iteration is good.

It is actually possible to improve the performance with a logarithmic-time algorithm. Consider the matrices

m = \begin{pmatrix} 1 & 1 \\ 1 & 0 \end{pmatrix}, m^2 = \begin{pmatrix} 2 & 1 \\ 1 & 1 \end{pmatrix}, m^3 = \begin{pmatrix} 3 & 2 \\ 2 & 1 \end{pmatrix}, m^4 = \begin{pmatrix} 5 & 3 \\ 3 & 2 \end{pmatrix}, m^5 = \begin{pmatrix} 8 & 5 \\ 5 & 3 \end{pmatrix}.

Each time the matrix is multiplied by itself, the number in the lower left-hand corner is the next fibonacci number; for instance, F4=3 (F0=0 is a special case). Of course, powering can be done using a binary square-and-multiply algorithm, as in the ipow and expm functions of the Standard Prelude, giving a logarithmic algorithm for computing the nth fibonacci number.

Your task is to write the three fibonacci functions — exponential, linear, and logarithmic — described above. When you are finished, you are welcome to read or run a suggested solution, or to post your own solution or discuss the exercise in the comments below.


Re: Rapidly navigating buffers using search

comp.lang.scheme - Wed, 07/28/2010 - 13:00
ORACLE by Larry Ellison is a more dangerous monopoly with boundless
GREED
Bill Gates is a decent family man and a genuine PHILANTHROPIST
ORACLE by Larry Ellison is a more dangerous monopoly with boundless
GREED
Bill Gates is a decent family man and a genuine PHILANTHROPIST
ORACLE by Larry Ellison is a more dangerous monopoly with boundless

Programming Praxis: HAMURABI.BAS

Planet Scheme - Tue, 07/27/2010 - 10:00

Back in the 1970s, David Ahl wrote a new game program each month for Creative Computing magazine. Those were the days of all-caps teletypes (if you were rich you could get a new-fangled “glass teletype”) and punched paper tapes (it was fun to play with the confetti they made). MS-BASIC permitted twenty-six single-letter variable names; later they also allowed a single letter followed by a single digit. There were no user-defined functions and no recursion. GOTO was common, resulting in a phenomenon called “spaghetti code.” There was good news, however: it was acceptable programming practice to GOTO the middle of a FOR loop and run the code there, as long as you jumped back out of the loop before the corresponding NEXT — try to do that in your favorite functional language!

One of Ahl’s most memorable games was Hamurabi, in which the player took the role of the administrator of the ancient city of Sumeria, managing the grain and land resources of the city and trying to keep the residents from starvation. It is typical of the genre, with simple numeric input and scrolling text output. Here is a description and sample game, and the original BASIC source code is reproduced on the next page. By my count, there are fourteen lines that are unreachable except by an IF…THEN, GOSUB or GOTO, forty-three lines that redirect control flow away from the line below, and four instances (line 555 to 215, bypassing line 210, 453 and 479 to 440, bypassing 430, 441 to 511, bypassing 510, and 880 and 885 to 565, bypassing 560) of jumping into the middle of a block of code; that’s a fine bowl of spaghetti, considering the entire program is only 120 lines. Variable P represents the current population, S is the number of bushels in stores, and A is the number of acres of farmland owned by the city, but other variables are used inconsistently — for instance D sometimes represents the number of deaths in the current year, but other times it represents the current input value, and other times Q is used to represent the current input value.

Your task is to reimplement HAMURABI.BAS in a more modern computer language. Don’t peek at the solution unless you want to deprive yourself of the sheer joy of working out the spaghetti code and figuring out what the variables really stand for. When you are finished, you are welcome to read or run a suggested solution, or to post your own solution or discuss the exercise in the comments below.


Grant Rettke: My old leather coat

Planet Scheme - Mon, 07/26/2010 - 02:23

While waiting for the Roadcrafter suit to arrive; I decided to get my old leather coat out of storage. Purchased at the flea market in Orange County, CA sometime in the mid-nineties, I’d somehow managed never to wear it. While some may lament the 90’s shoulder-pad styling, it is hard not to like the southwestern influenced design.

Thus far it has been pretty comfortable, the leather seems sturdy, and you know… I don’t mind the smitten looks that I receive while wearing it one bit ;).

Grant Rettke: How would you handle this rust?

Planet Scheme - Mon, 07/26/2010 - 02:16

My Concours has a little rust-spot on the gas tank. The bike was recently serviced and they didn’t see any rust inside of the gas tank, so you know, I’ve got warm-fuzzies about that but I still need to do something about the rust. Here are some progressively more detailed photos of the bike and the rust-spot (click to zoom):

Talking to four different friends and co-workers, their advice is split two ways:

  1. Sand down the rust with wet-grit paper or a dremel and fix it immediately to prevent it from spreading further.
  2. Do not break the seal of the OEM paint. As long as the rust doesn’t spread; you don’t need to worry about it. Just leave it.

What would you do and why would you do that?

>>> Assembler Book - Read or Download Individual Chapters - Volume 5 Chapter One: Thunks <<<

comp.lang.scheme - Sat, 07/24/2010 - 14:00
Assembler Book - Read or Download Individual Chapters
Table of Contents and Index
Short Table of Contents (44KB)
PDF File
Full Table of Contents (408KB)
PDF File
Index (724KB)
PDF File
Volume One - Data Representation (40K)
Chapter One: Foreward (60K)
PDF File
Chapter Two: Hello, World of Assembly (316 K)

See Hot College Girls Latest Sex Videos.

comp.lang.scheme - Fri, 07/23/2010 - 20:00
See Hot College Girls Latest Sex Videos. At [link]
Due to high sex content, i have hidden the videos in an image.
in that website on Top Side search box Above click on image and watch
videos in all angles. please don,t tell to anyone.

Google App Inventor compiler written in Scheme

comp.lang.scheme - Fri, 07/23/2010 - 19:00
From [link]
The compiler that translates the visual blocks language for
implementation on Android uses the Kawa Language Framework and Kawa's
dialect of the Scheme programming language, developed by Per Bothner and
distributed as part of the Gnu Operating System by the Free Software
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