I'm brand new to programming and I've been searching for a route to learning
it. I've touched on C++ and have been off on about going that way (it seems
incredibly complicated to the point of discouraging) or going with Java (it
seems incredibly popular and that's about all I know about it) or starting
with Dr. Scheme in an online tutorial that looks kinda interesting. It's
"How to Design Programs" by Matthias Felleisen, Robert Bruce Findler,
Matthew Flatt, & Shriram Krishnamurthi from MIT press. The whole book @
http://www.htdp.org/
I'm wondering if anyone here is familiar with that course. And if anyone
would care to comment about starting this way. What's the drawbacks of
starting with Lisp, if any? What are the advantages? What's the time factor
in getting up and running and doing practical, useful things with it versus
the time factor for other languages? I cannot tell you exactly where I want
to go with it; I'm too new to the whole thing. I can tell you that I'm going
to graduate soon with a CS degree and I can't program. I can tell you that I
want to work with databases for a competitive edge in a business I want to
start in healthcare that can branch out in many different directions, from
home health to community outreach.
I'm lost.
Why Lisp?
"J Swift" <····@hotmail.CUT.com> writes:
> Why Lisp?
Because it rocks! For my more extensive answer to that question check
out:
<http://www.gigamonkeys.com/book/>
-Peter
--
Peter Seibel ·····@javamonkey.com
Lisp is the red pill. -- John Fraser, comp.lang.lisp
On Fri, 11 Feb 2005 04:53:11 +0000, Peter Seibel wrote:
> "J Swift" <····@hotmail.CUT.com> writes:
>
>> Why Lisp?
>
> Because it rocks! For my more extensive answer to that question check
> out:
>
> <http://www.gigamonkeys.com/book/>
>
> -Peter
What's that? It's full of rocks. :) Seriously I've heard some people
advocate that at least once in a programmers career they should be exposed
to something low-level. Like say assembly, just so they know what happens
behind the scenes, and hopefully will write better code.
From: Christopher C. Stacy
Subject: Re: Where you can you go with Lisp?
Date:
Message-ID: <ull9v2ue8.fsf@news.dtpq.com>
BR <··········@comcast.net> writes:
> On Fri, 11 Feb 2005 04:53:11 +0000, Peter Seibel wrote:
>
> > "J Swift" <····@hotmail.CUT.com> writes:
> >
> >> Why Lisp?
> >
> > Because it rocks! For my more extensive answer to that question check
> > out:
> >
> > <http://www.gigamonkeys.com/book/>
> >
> > -Peter
>
> What's that? It's full of rocks. :) Seriously I've heard some people
> advocate that at least once in a programmers career they should be exposed
> to something low-level. Like say assembly, just so they know what happens
> behind the scenes, and hopefully will write better code.
A little knowledge is a dangerous thing.
······@news.dtpq.com (Christopher C. Stacy) writes:
> A little knowledge is a dangerous thing.
A little learning is a dangerous thing;
Drink deep, or taste not the Pierian spring:
There shallow draughts intoxicate the brain,
And drinking largely sobers us again.
Alexander Pope, Essay on Criticism. Part ii. Line 15.
--
David Magda <dmagda at ee.ryerson.ca>, http://www.magda.ca/
Because the innovator has for enemies all those who have done well under
the old conditions, and lukewarm defenders in those who may do well
under the new. -- Niccolo Machiavelli, _The Prince_, Chapter VI
From: Rahul Jain
Subject: Re: Where you can you go with Lisp?
Date:
Message-ID: <87acpyd2y0.fsf@nyct.net>
BR <··········@comcast.net> writes:
> What's that? It's full of rocks. :) Seriously I've heard some people
> advocate that at least once in a programmers career they should be exposed
> to something low-level. Like say assembly, just so they know what happens
> behind the scenes, and hopefully will write better code.
No, you don't learn that from learning assembly. You learn that from
studying computer architecture. Assembly code doesn't have anything to
do with what actually happens behind the scenes in any detailed way. For
example, loop unrolling makes no sense in the context of just assembly
code, but makes perfect sense given certain types of branch predictors,
pipelines, and reorder buffering (or, more importantly, lack thereof).
A particularly interesting question is: Why is loop unrolling very
important when executing on the Cell processor's SPEs but possibly
harmful when executing on a Pentium 4? As a followup: Is it more or less
harmful on a Pentium 4 or Pentium M and why? Learning either of the
assembly languages involved will give no insight into the answers to
such questions.
--
Rahul Jain
·····@nyct.net
Professional Software Developer, Amateur Quantum Mechanicist
To J Swift: welcome! A good combination of reading for you may be the
Felleisen book and Peter Seibel's book in the previous post.
Felleisen's books introduce programming in small steps, magically
arranged so each step is really cool. I'm thinking of The Little
Schemer (former The Little Lisper) and The Seasoned Schemer. Seibel's
book is regarded as great for getting you to practical things quickly
(hence his title, Practical Common Lisp). Your phrases "database" and
"competitive edge" suggest you'd like some practical stuff in your mix.
Two more:
Abelson and Sussman, Structure and Interpretation of Computer Programs
(Felleisenesque but thicker)
Paul Graham, On Lisp (my personal favorite) online at
http://www.paulgraham.com/onlisp.html
If you talk with friends or professors over lunch, they'll tell you
Lisp is old-fashioned and unmarketable. Do not believe them. Lisp
will give you an incredible foundation in programming--how to think as
a programmer. Then read this group and the wikis to learn how it fits
into corporate America.
<···············@yahoo.com> wrote in message
·····························@z14g2000cwz.googlegroups.com...
> To J Swift: welcome! A good combination of reading for you may be the
> Felleisen book and Peter Seibel's book in the previous post.
> Felleisen's books introduce programming in small steps, magically
> arranged so each step is really cool. I'm thinking of The Little
> Schemer (former The Little Lisper) and The Seasoned Schemer. Seibel's
> book is regarded as great for getting you to practical things quickly
> (hence his title, Practical Common Lisp). Your phrases "database" and
> "competitive edge" suggest you'd like some practical stuff in your mix.
>
> Two more:
> Abelson and Sussman, Structure and Interpretation of Computer Programs
> (Felleisenesque but thicker)
> Paul Graham, On Lisp (my personal favorite) online at
> http://www.paulgraham.com/onlisp.html
Thanks for the welcome and the list of books. I checked out the editorial
review for Practical Common Lisp--it's not out yet, is it? Sounds good.
You're right about me looking for practical applications. Because I've heard
that Lisp can save time in writing code is one reason why I'm interested.
I'm not into programming at all... I'm into what programming can do, and the
faster the better.
<snip>
"J Swift" <····@hotmail.CUT.com> writes:
> Thanks for the welcome and the list of books. I checked out the
> editorial review for Practical Common Lisp--it's not out yet, is it?
Not yet. However, the whole text (in draft, pre-copy edit form) is online at:
<http://www.gigamonkeys.com/book/>
The dead-tree version should be out some time in April.
-Peter
--
Peter Seibel ·····@javamonkey.com
Lisp is the red pill. -- John Fraser, comp.lang.lisp
"Peter Seibel" <·····@javamonkey.com> wrote in message
···················@javamonkey.com...
> "J Swift" <····@hotmail.CUT.com> writes:
>
>> Thanks for the welcome and the list of books. I checked out the
>> editorial review for Practical Common Lisp--it's not out yet, is it?
>
> Not yet. However, the whole text (in draft, pre-copy edit form) is online
> at:
>
> <http://www.gigamonkeys.com/book/>
>
> The dead-tree version should be out some time in April.
>
> -Peter
Thanks! I definitely plan to check it out.
Up spake J Swift:
> I'm brand new to programming and I've been searching for a route to
> learning it.
>
> I've touched on C++ [and] Java
Both Java and C++ are VERY BAD choices of first language[0]. They are
what I would call "heavyweight" languages -- designed for doing real
work. As a result, they can be pedantic about things that confuse
newbies. I would also class Common Lisp as a "heavyweight" language.
The last time I spoke on this subject I said this:
http://twb.ath.cx/wiki/LinuxQuestions.html#sec1 ...wherein I make the
case that WHAT you want to learn should guide your choice of first
language.
It's rather vague about Scheme, since I was only then starting to look
seriously at Lispen at that time. I've since tried DrScheme and think
it's an excellent choice for a teaching environment / language; dunno
what textbook to recommend.
If you start with Scheme, I can confidently predict that you will be
confused by the distinction between a variable and it's value, as
manifest in the QUOTE operator. A little C or Assembly background is
helpful here, since both those languages deal with pointers directly.
> I can tell you I'm going to graduate soon with CS degree and I can't
> program.
OK, so presumably you're not a total newbie. Granted that programming
is only part of Computer Science, but it's a significant part. If
you're about to graduate, what HAVE they been teaching you?
[0] Unfortunately this hasn't stopped universities rushing to adopt Java
as the core first-year language :-/
"Trent Buck" <·········@tznvy.pbz> wrote in message
····························@harpo.marx...
<snip>
> OK, so presumably you're not a total newbie. Granted that programming
> is only part of Computer Science, but it's a significant part. If
> you're about to graduate, what HAVE they been teaching you?
I can figure things out and slap things together for assignments. I can take
someone elses code, from texts and the internet, etc. and work with it...
and it works, that's all I know. That gets me by and has gotten me by, with
pretty good grades too, but it takes a long time for me do anything... I've
an overview of the whole field, a lot of subjects and a lot of work, but no
concentration anywhere. I also work full time (but not with anything
computer related) and now that school is out maybe I'll have some time to
really learn.
<snip>
On Fri, 11 Feb 2005 07:15:30 +0000, Trent Buck wrote:
> Up spake J Swift:
>> I'm brand new to programming and I've been searching for a route to
>> learning it.
>>
>> I've touched on C++ [and] Java
>
> Both Java and C++ are VERY BAD choices of first language[0]. They are
> what I would call "heavyweight" languages -- designed for doing real
> work. As a result, they can be pedantic about things that confuse
> newbies. I would also class Common Lisp as a "heavyweight" language.
>
> The last time I spoke on this subject I said this:
> http://twb.ath.cx/wiki/LinuxQuestions.html#sec1 ...wherein I make the
> case that WHAT you want to learn should guide your choice of first
> language.
>
> It's rather vague about Scheme, since I was only then starting to look
> seriously at Lispen at that time. I've since tried DrScheme and think
> it's an excellent choice for a teaching environment / language; dunno
> what textbook to recommend.
Take a look at Structure and Interpretation of Programming Languages by
Abelson and Sussman: http://mitpress.mit.edu/sicp/
>
> If you start with Scheme, I can confidently predict that you will be
> confused by the distinction between a variable and it's value, as
> manifest in the QUOTE operator. A little C or Assembly background is
> helpful here, since both those languages deal with pointers directly.
>
>> I can tell you I'm going to graduate soon with CS degree and I can't
>> program.
>
> OK, so presumably you're not a total newbie. Granted that programming
> is only part of Computer Science, but it's a significant part. If
> you're about to graduate, what HAVE they been teaching you?
>
> [0] Unfortunately this hasn't stopped universities rushing to adopt Java
> as the core first-year language :-/
At the Vrije Universiteit Brussel (http://we.vub.ac.be/),
the first language new students are confronted with, is Scheme.
I haven't regret a moment choosing this university for my studies.
Up spake GuyBrush Treepwood:
> > It's rather vague about Scheme, since I was only then starting to look
> > seriously at Lispen at that time. I've since tried DrScheme and think
> > it's an excellent choice for a teaching environment / language; dunno
> > what textbook to recommend.
>
> Take a look at Structure and Interpretation of Programming Languages by
> Abelson and Sussman: http://mitpress.mit.edu/sicp/
Yeah, but I worry there may be discrepancies between the different
flavours of scheme DrScheme provides and what the SICP exercises expect.
When I went through SICP I used GNU/MIT Scheme (mit-scheme under
Debian), which is modern descendant of what Sussman's students were
using.
--
-trent
The best answer when anybody asks you if you're any good with explosives
is to hold up two open hands and simply say "Ten". -- adb
Not enough discrepancies to stop the original poster, right? SICP
starts with (define ...) with numbers and functions, eventually moves
on to closures....
Trent Buck <·········@tznvy.pbz> writes:
> Up spake GuyBrush Treepwood:
> > > It's rather vague about Scheme, since I was only then starting to look
> > > seriously at Lispen at that time. I've since tried DrScheme and think
> > > it's an excellent choice for a teaching environment / language; dunno
> > > what textbook to recommend.
> >
> > Take a look at Structure and Interpretation of Programming Languages by
> > Abelson and Sussman: http://mitpress.mit.edu/sicp/
>
> Yeah, but I worry there may be discrepancies between the different
> flavours of scheme DrScheme provides and what the SICP exercises expect.
If I recall it correctly, the current edition of SICP works with any
standard-compliant Scheme implementation. (I think this was different
at the past.)
At my university we teach CS using DrScheme + SICP for a while now and
it works quite well.
Up spake Matthias:
> > Yeah, but I worry there may be discrepancies between the different
> > flavours of scheme DrScheme provides and what the SICP exercises expect.
>
> If I recall it correctly, the current edition of SICP works with any
> standard-compliant Scheme implementation. (I think this was different
> at the past.)
>
> At my university we teach CS using DrScheme + SICP for a while now and
> it works quite well.
Glad to hear it. I won't worry about that anymore :-)
--
-trent
...like my pickup line: move I need a drink.
Trent Buck wrote:
> Yeah, but I worry there may be discrepancies between the different
> flavours of scheme DrScheme provides and what the SICP exercises expect.
No problems there.
<http://schemecookbook.org/view/Cookbook/MiscSICP>
--
Jens Axel Søgaard
On Fri, 11 Feb 2005 07:15:30 +0000, Trent Buck wrote:
> Up spake J Swift:
>> I'm brand new to programming and I've been searching for a route to
>> learning it.
>>
>> I've touched on C++ [and] Java
>
> Both Java and C++ are VERY BAD choices of first language[0]. They are
> what I would call "heavyweight" languages -- designed for doing real
> work. As a result, they can be pedantic about things that confuse
> newbies. I would also class Common Lisp as a "heavyweight" language.
>
> The last time I spoke on this subject I said this:
> http://twb.ath.cx/wiki/LinuxQuestions.html#sec1 ...wherein I make the
> case that WHAT you want to learn should guide your choice of first
> language.
>
> It's rather vague about Scheme, since I was only then starting to look
> seriously at Lispen at that time. I've since tried DrScheme and think
> it's an excellent choice for a teaching environment / language; dunno
> what textbook to recommend.
I'm not sure why you would think scheme's any easier for a newbie than
common lisp. You can learn common lisp using similar steps you would to
learn scheme. The only times they significantly diverge is the whole
lisp-1 / lisp-2 difference (which I assert has little to no impact on how
difficult it is to learn the language) and difference in availability of
various utilities and control constructs. I've never known Common Lisp to
be "pedantic" in any "heavyweight language" sense. You have the option of
being pedantic like you're forced to in a weakly typed language such as C,
but it's completely optional. That option is yet another reason to go for
lisp - you can start off simple, and learn how to make your code more
efficient when you're ready for it rather than being forced to always or
never think about that sort of thing.
I'm spending way too much time on usenet today :(
Robert Marlow <··········@bobturf.org> schrieb:
> I'm not sure why you would think scheme's any easier for a newbie than
> common lisp. You can learn common lisp using similar steps you would
> to learn scheme. The only times they significantly diverge is the
> whole lisp-1 / lisp-2 difference (which I assert has little to no
> impact on how difficult it is to learn the language) and difference in
> availability of various utilities and control constructs.
The concepts are not fundamentally different but, as pointed out
already, Scheme is generally more consistent. I also think Scheme's
smaller standard library is good for *learning* because it's more clear
what the "right way" to do any given thing is -- you don't get questions
like "what's the difference between setf and setq?" right off. Finally,
and most importantly, DrScheme is designed for teaching and so it can do
things like:
- Restrict the language to a smaller subset which initially avoids
certain confusing concepts like quoting a list
- Therefore offer clearer error messages
- Use the same syntax for print as for read
- Offer an easy-to-use editor with syntax highlighting and interpreter
integration (so you don't have to learn Emacs right away)
- And many other things besides.
The problem with Common Lisp for learning is it's hard to find a
widely-used subset of features that's actually useful. Like you can't
write an HOF without understanding namespaces and symbols, where in
Scheme you just need variables.
Robert Marlow schrieb:
> On Fri, 11 Feb 2005 07:15:30 +0000, Trent Buck wrote:
Hallo
Well its boring.
Allways the same story.
Its like beenig among joung childeren.
Please come together
lin
Confession: I finished Graham's "ANSI Common Lisp" before I looked at
Scheme; I learnt CL before Scheme. But by the time I started CL I had
most of a CS degree under my belt and was trying to write MAPCAR in C
macros.
Up spake Robert Marlow:
> I'm not sure why you would think scheme's any easier for a newbie than
> common lisp.
Off the top of my head:
- Scheme is small. Stuff like packages aren't needed for beginners.
You could teach introductory CL and not mention them, but they'd
still be in e.g. the online documentation.
- Single namespace for functions and variables. As a result, you can
avoid / delay explaining why you need FUNCALL and FUNCTION, and the
question of "what *is* a symbol, really?".
- A more consistent naming scheme -- '?' for predicates, '!' for
destructive functions, and so on.
I guess my overall argument is that Scheme is by design a small, simple
Lisp for teaching. It makes sense to me to use it for teaching
beginners, and move them to something more powerful (i.e. Common Lisp)
once they grok the fundamentals.
Similarly, I recommend teaching C before C++ or Java, because I've SEEN
courses which try to teach Java as a first language and the students
simply can't cope. They end up trying to memorize the Java API instead
of actually UNDERSTANDING what is happening in the system.
PS: I didn't really mean to lump CL with Java and C++ in my previous
post :-)
--
-trent
How can you think you matter when your homepage has a tilde in it?
I took the liberty of clicking on your name in google groups and
looking at your recent posts, which were for help with homework.. it
seems that your problem is, like you said, that you don't know how to
program. Programming in any language is giving really, really,
explicit instructions to a really, really stupid machine, which does
exactly what you ask, no more, no less. It seems that you haven't
learned to express your thoughts in the explicit way that programming
requires. I was in that situation myself, and HTDP helped me improve
my skills at both translating what I wanted into something a computer
could understand, and making it clean enough that I could understand it
too. Once you can do that, learning any language shouldn't be too
difficult. I am aware of no better book than HTDP for helping a newbie
learn to program, though one may exist.
HTDP uses Scheme, which is a good language to learn with because it's
extremely simple. With C++ (which I tried and failed to start with)
you have to learn a complicated syntax and OO right from the start,
along with learning how to program. It's a bit much to take in one
bite. Don't worry about whether you will ever use Scheme in real life,
because it doesn't take long to learn the subset of it used in HTDP.
Right now you need to focus on learning to think about programming, not
on any particular tools.
BTW, here's a solution to one of the C++ problems you asked about, in
Common Lisp:
(defun f ()
(format t "Number of rooms ")
(let* ((rooms (loop for i from 1 to (read)
do (format t "Room dimension: ")
collect `(,(read) ,(read)))))
(loop for i in rooms sum (* (first i) (second i)) into area
finally (format t "Total area of the rooms = ~A~%" area))
(let ((largest
(first (sort rooms
#'(lambda (x y) (> (+ (first x) (second x))
(+ (first y) (second y))))))))
(format t "Room with largest perimeter is ~A x ~A~%"
(first largest) (second largest)))))
It's kind of ugly, but it took very little time to write (and I'm no
guru), and it's a lot shorter than the C++ version.
<··········@gmail.com> wrote in message
·····························@f14g2000cwb.googlegroups.com...
>I took the liberty of clicking on your name in google groups and
> looking at your recent posts, which were for help with homework.. it
> seems that your problem is, like you said, that you don't know how to
> program. Programming in any language is giving really, really,
> explicit instructions to a really, really stupid machine, which does
> exactly what you ask, no more, no less. It seems that you haven't
> learned to express your thoughts in the explicit way that programming
> requires. I was in that situation myself, and HTDP helped me improve
> my skills at both translating what I wanted into something a computer
> could understand, and making it clean enough that I could understand it
> too. Once you can do that, learning any language shouldn't be too
> difficult. I am aware of no better book than HTDP for helping a newbie
> learn to program, though one may exist.
>
> HTDP uses Scheme, which is a good language to learn with because it's
> extremely simple. With C++ (which I tried and failed to start with)
> you have to learn a complicated syntax and OO right from the start,
> along with learning how to program. It's a bit much to take in one
> bite. Don't worry about whether you will ever use Scheme in real life,
> because it doesn't take long to learn the subset of it used in HTDP.
> Right now you need to focus on learning to think about programming, not
> on any particular tools.
I have lately considered NOT doing HTDP for various reasons, one being why
learn a language that you may not end up using. But you've confirmed for me
that maybe I'd better go down the that road first. Because your right, with
C++ I have gotten bogged down with the wieght of the syntax and have not
felt the joy of expressing my thoughts in the explicit way that programming
requires. Thanks for the example of code in Lisp that I did in C++. BTW,
does Lisp do OO?
>
> BTW, here's a solution to one of the C++ problems you asked about, in
> Common Lisp:
>
> (defun f ()
> (format t "Number of rooms ")
> (let* ((rooms (loop for i from 1 to (read)
> do (format t "Room dimension: ")
> collect `(,(read) ,(read)))))
> (loop for i in rooms sum (* (first i) (second i)) into area
> finally (format t "Total area of the rooms = ~A~%" area))
> (let ((largest
> (first (sort rooms
> #'(lambda (x y) (> (+ (first x) (second x))
> (+ (first y) (second y))))))))
> (format t "Room with largest perimeter is ~A x ~A~%"
> (first largest) (second largest)))))
>
>
> It's kind of ugly, but it took very little time to write (and I'm no
> guru), and it's a lot shorter than the C++ version.
>
"J Swift" <····@hotmail.CUT.com> writes:
> <··········@gmail.com> wrote in message
> ·····························@f14g2000cwb.googlegroups.com...
>>I took the liberty of clicking on your name in google groups and
>> looking at your recent posts, which were for help with homework.. it
>> seems that your problem is, like you said, that you don't know how to
>> program. Programming in any language is giving really, really,
>> explicit instructions to a really, really stupid machine, which does
>> exactly what you ask, no more, no less. It seems that you haven't
>> learned to express your thoughts in the explicit way that programming
>> requires. I was in that situation myself, and HTDP helped me improve
>> my skills at both translating what I wanted into something a computer
>> could understand, and making it clean enough that I could understand it
>> too. Once you can do that, learning any language shouldn't be too
>> difficult. I am aware of no better book than HTDP for helping a newbie
>> learn to program, though one may exist.
>>
>> HTDP uses Scheme, which is a good language to learn with because it's
>> extremely simple. With C++ (which I tried and failed to start with)
>> you have to learn a complicated syntax and OO right from the start,
>> along with learning how to program. It's a bit much to take in one
>> bite. Don't worry about whether you will ever use Scheme in real life,
>> because it doesn't take long to learn the subset of it used in HTDP.
>> Right now you need to focus on learning to think about programming, not
>> on any particular tools.
>
> I have lately considered NOT doing HTDP for various reasons, one being why
> learn a language that you may not end up using. But you've confirmed for me
> that maybe I'd better go down the that road first. Because your right, with
> C++ I have gotten bogged down with the wieght of the syntax and have not
> felt the joy of expressing my thoughts in the explicit way that programming
> requires. Thanks for the example of code in Lisp that I did in C++. BTW,
> does Lisp do OO?
Yes. (However, be aware that "OO" is not really well defined. You can
easily find partisans of one language or another that "does OO" in a
particular way who will tell you that other languages "don't" or
"don't really" do OO because those other languages don't do it exactly
the same way as their favorite langauge. And Common Lisp's way is
probably more different from most other languages than they are from
each other, if you get what I mean. We Lispers think it's
different/better but it is different.
-Peter
--
Peter Seibel ·····@javamonkey.com
Lisp is the red pill. -- John Fraser, comp.lang.lisp
J Swift wrote:
> I have lately considered NOT doing HTDP for various reasons, one being why
> learn a language that you may not end up using. But you've confirmed for me
> that maybe I'd better go down the that road first. Because your right, with
> C++ I have gotten bogged down with the wieght of the syntax and have not
> felt the joy of expressing my thoughts in the explicit way that programming
> requires. Thanks for the example of code in Lisp that I did in C++. BTW,
> does Lisp do OO?
>
>
The above example expressed in a more OO style:
(defclass rectangular-room ()
((width :initarg :width :accessor width)
(breadth :initarg :breadth :accessor breadth)))
(defmethod print-object ((room rectangular-room) stream)
(format stream "#<rectangular-room ~A x ~A>" (width room) (breadth
room)))
(defmethod perimeter ((room rectangular-room))
(* 2 (+ (width room) (breadth room))))
(defmethod area ((room rectangular-room))
(* (width room) (breadth room)))
(defun run-roomer ()
(format t "Number of rooms? ")
(let ((rooms (loop for i from 1 to (read)
do (format t "~%Room dimension: ")
collect (make-instance 'rectangular-room :width (read)
:breadth (read)))))
(format t "~%Total area of rooms = ~A~%" (loop for room in rooms
sum (area room)))
(format t "Room with largest perimeter is ~A~%"
(first (sort (copy-list rooms)
(lambda (r1 r2) (> (perimeter r1) (perimeter
r2))))))))
CL-USER 4 > (run-roomer)
Number of rooms? 3
Room dimension: 4 5
Room dimension: 6 5
Room dimension: 10 20
Total area of rooms = 250
Room with largest perimeter is #<rectangular-room 10 x 20>
NIL
CL-USER 5 >
Wade Humeniuk wrote:
> (defmethod print-object ((room rectangular-room) stream)
> (format stream "#<rectangular-room ~A x ~A>" (width room) (breadth
> room)))
Wouldn't it be better to use PRINT-UNREADABLE-OBJECT? That would print
things in a more conventional style (whatever the convention may be).
The code (untested) would look like this:
(defmethod print-object ((room rectangular-room) stream)
(print-unreadable-object (room stream :type t)
(format stream "~A x ~A" (width room) (breadth room))))
-Peter
J Swift wrote:
> BTW, does Lisp do OO?
It's probably the most complete OO language you can find on this planet.
For an "executive" summary, see http://www.lisp.org/table/objects.htm
Pascal
Pascal Costanza wrote:
> J Swift wrote:
>
>> BTW, does Lisp do OO?
>
> It's probably the most complete OO language you can find on this planet.
> For an "executive" summary, see http://www.lisp.org/table/objects.htm
>
How does it compare with Smalltalk?
I haven't had time to really look at that language yet, but it's suppposed
to be very object-oriented. Never mind the standard library; how do the
object systems compare?
From: Marco Baringer
Subject: Re: Where you can you go with Lisp?
Date:
Message-ID: <m2zmyaccof.fsf@soma.local>
Svein Ove Aas <·········@aas.no> writes:
> How does it compare with Smalltalk?
>
> I haven't had time to really look at that language yet, but it's suppposed
> to be very object-oriented. Never mind the standard library; how do the
> object systems compare?
The main difference between the two is that in smalltalk _everything_
is an object and the OO paradigm is the only one you have. Everything
in smalltalk is a message send on an object (even the conditional
operators). Common Lisp is multi paradigm, you can use classes and
generic functions (which is very distinct from message passing) but
you can also use a purly functional or purly iterative style.
The real difference, when using the two systems, is how unified things
feel. In SmallTalk you never see the end of the OO world (since that's
the only world you have in SmallTalk), in cl you do eventually attempt
to get the slot of a struct, or want to subclass HASH-TABLE, and
realize that some things aren't objects (not normal ones at least).
Afaict there's no difference in power or flexibiliy of the two (though
they are different and require different ways of looking at things).
--
-Marco
Ring the bells that still can ring.
Forget the perfect offering.
There is a crack in everything.
That's how the light gets in.
-Leonard Cohen
Marco Baringer <··@bese.it> schrieb:
> Svein Ove Aas <·········@aas.no> writes:
>> How does it compare with Smalltalk?
>
> The main difference between the two is that in smalltalk _everything_
> is an object and the OO paradigm is the only one you have. Everything
> in smalltalk is a message send on an object (even the conditional
> operators).
I think you were more right with the second sentence. In CL, like
Smalltalk, everything is an object in the sense that you can dispatch
generic functions off any type of value. In CL, unlike Smalltalk, some
functions are not generic, but this doesn't make much difference to
anything. I think the most important difference is rather that Smalltalk
only has single-dispatch.
J Swift wrote:
> I have lately considered NOT doing HTDP for various reasons, one being why
> learn a language that you may not end up using. But you've confirmed for me
> that maybe I'd better go down the that road first. Because your right, with
> C++ I have gotten bogged down with the wieght of the syntax and have not
> felt the joy of expressing my thoughts in the explicit way that programming
> requires. Thanks for the example of code in Lisp that I did in C++. BTW,
> does Lisp do OO?
What I like about HTDP is that concentrates on how to think when programming.
Using design recipes it teaches how to construct programs in a systematic
way. E.g. it teaches how the shape of a datastructure dictates how functions
working on them are constructed. Contrary to traditional "Learn to program
in XX"-books the focus are on concepts. These concepts should be easily
recognized, when moving on to other languages.
Note also, that HTDP doesn't teach Scheme as such - a limited subset is
used to illustrate the concepts.
--
Jens Axel Søgaard
··········@gmail.com writes:
> I was in that situation myself, and HTDP helped me improve my
> skills at both translating what I wanted into something a computer
> could understand, and making it clean enough that I could
> understand it too.
"HTDP"?
--
David Magda <dmagda at ee.ryerson.ca>, http://www.magda.ca/
Because the innovator has for enemies all those who have done well under
the old conditions, and lukewarm defenders in those who may do well
under the new. -- Niccolo Machiavelli, _The Prince_, Chapter VI
David Magda <··················@ee.ryerson.ca> writes:
> "HTDP"?
http://www.htdp.org (first hit with Google)
Paolo
--
Lisp Propulsion Laboratory log - http://www.paoloamoroso.it/log
Recommended Common Lisp libraries/tools (see also http://clrfi.alu.org):
- ASDF/ASDF-INSTALL: system building/installation
- CL-PPCRE: regular expressions
- UFFI: Foreign Function Interface
David Magda wrote:
> ··········@gmail.com writes:
>
>>I was in that situation myself, and HTDP helped me improve my
>>skills at both translating what I wanted into something a computer
>>could understand, and making it clean enough that I could
>>understand it too.
>
> "HTDP"?
The book "How To Design Programs", see
<http://www.htdp.org>
The main idea is to teach the reader *how to think* when programming.
Therefore it is very well suited for some one with no previous
programming experience.
--
Jens Axel Søgaard
On Thu, 10 Feb 2005 20:57:50 -0700, J Swift wrote:
> I'm brand new to programming and I've been searching for a route to learning
> it. I've touched on C++ and have been off on about going that way (it seems
> incredibly complicated to the point of discouraging) or going with Java (it
> seems incredibly popular and that's about all I know about it) or starting
> with Dr. Scheme in an online tutorial that looks kinda interesting. It's
> "How to Design Programs" by Matthias Felleisen, Robert Bruce Findler,
> Matthew Flatt, & Shriram Krishnamurthi from MIT press. The whole book @
> http://www.htdp.org/
>
> I'm wondering if anyone here is familiar with that course. And if anyone
> would care to comment about starting this way. What's the drawbacks of
> starting with Lisp, if any? What are the advantages? What's the time factor
> in getting up and running and doing practical, useful things with it versus
> the time factor for other languages? I cannot tell you exactly where I want
> to go with it; I'm too new to the whole thing. I can tell you that I'm going
> to graduate soon with a CS degree and I can't program. I can tell you that I
> want to work with databases for a competitive edge in a business I want to
> start in healthcare that can branch out in many different directions, from
> home health to community outreach.
>
> I'm lost.
>
> Why Lisp?
Lisp is very elegant and powerful. When you program you essentially have
to think in the language you're programming in. I personally find it much
easier to think in lisp than other languages, particularly imperative
ones like C which make you think more like a computer than an intelligent
being. Explaining the power of lisp will probably be lost on you if you
haven't encountered programming before. My suggestion would be to just try
it.
The disadvantage of learning lisp is you may end up only learning
lisp. After learning and using lisp I hate every moment I have to spend
with other languages due to their lack of powerful lisp-ish idioms (you
need lisp for lisp macros) or simply terrible syntax. For that reason,
some people may prefer to start with other languages and graduate to lisp
when they realise they're feeling dissatisfied or are looking for
enlightenment.
I don't imagine any language will assist you in getting to write useful
applications quicker(*) - all languages have fundamental
programming concepts you'll need to learn, but if you learn those concepts
in lisp I'm confident you'll be able to write applications more quickly
once you're ready to begin writing than you would with other languages.
(*) except perhaps languages lacking basic ideas like recursion but then
you're only learning quicker because you're getting a watered down
experience of programming. Taking this idea to the extreme, if you want no
watering down whatsoever and the full flavour programming offers, you'll
need lisp.
In article <········@nntp.zianet.com>, J Swift wrote:
> I'm brand new to programming and I've been searching for a route to learning
> it. I've touched on C++ and have been off on about going that way (it seems
> incredibly complicated to the point of discouraging) or going with Java (it
> seems incredibly popular and that's about all I know about it) or starting
> with Dr. Scheme in an online tutorial that looks kinda interesting. It's
> "How to Design Programs" by Matthias Felleisen, Robert Bruce Findler,
> Matthew Flatt, & Shriram Krishnamurthi from MIT press. The whole book @
> http://www.htdp.org/
HTDP is an /extraordinarily/ good book. If you go through it and do
the exercises, you will know how to program at the end. The reason to
use Scheme (and DrScheme in particular) is because that textbook uses
the DrScheme environment.
--
Neel Krishnaswami
·····@cs.cmu.edu
On Thu, 10 Feb 2005 20:57:50 -0700, "J Swift" <····@hotmail.CUT.com>
wrote:
>I'm wondering if anyone here is familiar with that course. And if anyone
>would care to comment about starting this way. What's the drawbacks of
>starting with Lisp, if any? What are the advantages? What's the time factor
>in getting up and running and doing practical, useful things with it versus
>the time factor for other languages? I cannot tell you exactly where I want
>to go with it; I'm too new to the whole thing. I can tell you that I'm going
>to graduate soon with a CS degree and I can't program. I can tell you that I
>want to work with databases for a competitive edge in a business I want to
>start in healthcare that can branch out in many different directions, from
>home health to community outreach.
>
>I'm lost.
>
>Why Lisp?
>
If you think about working in so called Information Technology,
don't waste your time learning Lisp. Nobody, repeat, NOBODY in the
industry is using Lisp except the fanatics on this group. However,
these guys will not hire you and will not pay your bills.
Learn Java, especially J2EE, what becomes the dominating platform in
the industry. Don't learn C++, its future is past. Learn C# and .NET
platform. It is more and more popular within the industry. Learn SQL
if you want to work with databases.
A.L.
A.L. wrote:
> If you think about working in so called Information Technology,
> don't waste your time learning Lisp. Nobody, repeat, NOBODY in the
> industry is using Lisp except the fanatics on this group. However,
> these guys will not hire you and will not pay your bills.
>
> Learn Java, especially J2EE, what becomes the dominating platform in
> the industry. Don't learn C++, its future is past. Learn C# and .NET
> platform. It is more and more popular within the industry. Learn SQL
> if you want to work with databases.
I actually fully agree. Lisp does not support Manager Oriented
Programming well. In fact, we have this saying: "To become a computer
nerd, you first need to learn how to run with the herd."
Incidentally, it'll be a great test of this usenet group to see whether
people can deal with this troll without getting too serious... after
all, there are at least 4 commercial Common Lisp implementors which
charge from $200-20,000/seat.
That said though, there do exist drawbacks to starting out with Lisp,
depending on your computing platform. But I use Common Lisp to co-opt
advantages of other tools, rather than senselessly compete. (Such as
generating Java and PHP code, so you don't actually see Lisp in the
final product, though it was heavily used).
MfG,
Tayssir
Tayssir John Gabbour wrote:
> A.L. wrote:
>> If you think about working in so called Information Technology,
>> don't waste your time learning Lisp. Nobody, repeat, NOBODY in the
>> industry is using Lisp except the fanatics on this group. However,
>> these guys will not hire you and will not pay your bills.
>>
>> Learn Java, especially J2EE, what becomes the dominating platform
>> in the industry. Don't learn C++, its future is past. Learn C#
>> and .NET platform. It is more and more popular within the industry.
>> Learn SQL if you want to work with databases.
>
> Incidentally, it'll be a great test of this usenet group to see
> whether people can deal with this troll without getting too
> serious... after all, there are at least 4 commercial Common Lisp
> implementors which charge from $200-20,000/seat.
But I do wish there were thoughtful, experienced critics. Not the kind
who fire easy salvos and run, but people like the Java BileBlog guy who
can analyze something in detail. There needs to be a level of honesty,
or it's boring.
People can really get away with calling Lisp users fanatics, if it's
part of a compelling case. But with posts like this, it's just not
honest. And therefore duller than it could be.
MfG,
Tayssir
A.L. wrote:
> On Thu, 10 Feb 2005 20:57:50 -0700, "J Swift" <····@hotmail.CUT.com>
> wrote:
>
> > I'm wondering if anyone here is familiar with that course. And if
> > anyone would care to comment about starting this way. What's the
> > drawbacks of starting with Lisp, if any? What are the advantages?
> > What's the time factor in getting up and running and doing
> > practical, useful things with it versus the time factor for other
> > languages? I cannot tell you exactly where I want to go with it;
> > I'm too new to the whole thing. I can tell you that I'm going to
> > graduate soon with a CS degree and I can't program. I can tell you
> > that I want to work with databases for a competitive edge in a
> > business I want to start in healthcare that can branch out in many
> > different directions, from home health to community outreach.
> >
> > I'm lost.
> >
> > Why Lisp?
> >
>
> Nobody, repeat, NOBODY in the
> industry is using Lisp except the fanatics on this group.
And what industry would that be? There are several companies/industries
that do use Lisp. I use it plenty at work (and most of our work is done
in C/C++).
> Learn Java, especially J2EE, what becomes the dominating platform in
> the industry.
Again, which industry? You seem to have a very narrow perspective of
what programmers do. Java is good for web sites and headaches. That's
it. I seriously can't believe that cell phone companies adopted it
(J2ME) for mobile phone development, but oh well. BREW is much better.
> Don't learn C++, its future is past. Learn C# and .NET platform.
You don't get out much, do you? I highly doubt that Java was written in
Java, and neither was C#. Who is being fanatical now? Meh... I'm
starting to smell a troll.
> Learn SQL if you want to work with databases.
This is good advice. I would also add to not learn SQL in Microsoft
Access, which is MS's personal flavor of SQL. Learn some of the more
standard ones and you'll be able to pick up MS's easier than the other
way around (that was my experience, at least).
There is nothing wrong with learning Java or C#. Both are fine
languages, and having another bullet point on the resume never hurts.
However, learning Lisp, Smalltalk, Forth, Haskell, etc might not be
able to [initially] land you an "industry" job, but the lessons learned
from them can be passed onto other languages you use in the future. And
there is nothing stopping you from actively seeking out a job using
those languages or starting your own company.
To the OP: Every single one of the programmers under me at work that
had experience with Lisp or Scheme in college is a 10x (at least)
better programmer than those that didn't. You're in college. Why *not*
take the course? What have you got to lose? You may find you love it or
hate it. But I can promise that if you love it, you'll hate your future
C++ classes. Good luck! :)
Jeff M.
--
http://www.retrobyte.org
··············@gmail.com
"A.L." schrieb:
> On Thu, 10 Feb 2005 20:57:50 -0700, "J Swift" <····@hotmail.CUT.com>
> wrote:
> >Why Lisp?
> If you think about working in so called Information Technology,
> don't waste your time learning Lisp. Nobody, repeat, NOBODY in the
> industry is using Lisp except the fanatics on this group. However,
> these guys will not hire you and will not pay your bills.
> Learn Java, especially J2EE, what becomes the dominating platform in
> the industry. Don't learn C++, its future is past. Learn C# and .NET
> platform. It is more and more popular within the industry. Learn SQL
> if you want to work with databases.
Ei nice. Very nice. It seems you are right. It seems so. But...
...in the 1960 you would say learn assembler
...in the 1970 this changed to fortran and c
...in 1980 it is called...
...in 1990 oh, come on.
We do see this happens.
Now, what did not change???
Right.
Some industry-bosses will realized on day, that there is a lot of money
that can be saved. And there are always some who play what the
mainstream plays, say ping-pong, eh?
lin
On Mon, 14 Feb 2005 11:26:50 +0100, lin8080 wrote:
> Ei nice. Very nice. It seems you are right. It seems so. But...
>
> ...in the 1960 you would say learn assembler ...in the 1970 this changed
> to fortran and c ...in 1980 it is called...
> ...in 1990 oh, come on.
>
> We do see this happens.
>
> Now, what did not change???
>
> Right.
>
> Some industry-bosses will realized on day, that there is a lot of money
> that can be saved. And there are always some who play what the
> mainstream plays, say ping-pong, eh?
Teach'em to think, and be done with it.
Up spake lin8080:
> Some industry-bosses will realized on day, that there is a lot of money
> that can be saved.
Oh, some of them realize that now. But thanks to things called
"budgetary estimates", they need to waste AT LEAST as much money as last
year, or they'll get less next year.
;-)
--
-trent
I still want a phone with caller-IQ. -- Tanuki
A.L. <·················@oddpost_tego_tez_nie.com> writes:
> If you think about working in so called Information Technology,
> don't waste your time learning Lisp. Nobody, repeat, NOBODY in the
> industry is using Lisp except the fanatics on this group. However,
> these guys will not hire you and will not pay your bills.
I don't understand this attitude. Even if you don't get to use Lisp
in a paying job, knowledge of the language and its techniques expands
your mind in ways that are quite portable to more mainstream
languages.
Even if I never get a Lisp gig, I will never think that Lisp was a
waste of my time.
--
An ideal world is left as an excercise to the reader.
--- Paul Graham, On Lisp 8.1
we programm almost exclusively in lisp at my job. there is
quite a bit of lisp in the EDA (electronic design automation)
industry.
-jim
David Steuber wrote:
> A.L. <·················@oddpost_tego_tez_nie.com> writes:
>
>
>>If you think about working in so called Information Technology,
>>don't waste your time learning Lisp. Nobody, repeat, NOBODY in the
>>industry is using Lisp except the fanatics on this group. However,
>>these guys will not hire you and will not pay your bills.
>
>
> I don't understand this attitude. Even if you don't get to use Lisp
> in a paying job, knowledge of the language and its techniques expands
> your mind in ways that are quite portable to more mainstream
> languages.
>
> Even if I never get a Lisp gig, I will never think that Lisp was a
> waste of my time.
>
Jim Newton wrote:
> we programm almost exclusively in lisp at my job. there is
> quite a bit of lisp in the EDA (electronic design automation)
> industry.
Is there more of Scheme than Common Lisp, though.
What are the significant VLSI CAD tools that can be
pointed to that are in CL as opposed to Scheme?
All I know was the in-house tool used by TI to design
the chip used in TI Explorer, but that was long ago, and
the chip, machine, and probably the tool have long
passed into history.
David Steuber wrote:
> A.L. <·················@oddpost_tego_tez_nie.com> writes:
>
>>If you think about working in so called Information Technology,
>>don't waste your time learning Lisp. Nobody, repeat, NOBODY in the
>>industry is using Lisp except the fanatics on this group. However,
>>these guys will not hire you and will not pay your bills.
>
> I don't understand this attitude. Even if you don't get to use Lisp
> in a paying job, knowledge of the language and its techniques expands
> your mind in ways that are quite portable to more mainstream
> languages.
>
> Even if I never get a Lisp gig, I will never think that Lisp was a
> waste of my time.
I can only guess that such an attitude develops from having great
difficulty with programming, and finding learning new languages to be
like trying to turn yourself inside out. The fallacy here is that like
everything else, programming becomes much less difficult with experience
and education. It's a sad, self fulfilling attitude.
-- MJF
"A.L." <·················@oddpost_tego_tez_nie.com> wrote in message
·······································@4ax.com...
> On Thu, 10 Feb 2005 20:57:50 -0700, "J Swift" <····@hotmail.CUT.com>
> wrote:
>
>>I'm wondering if anyone here is familiar with that course. And if anyone
>>would care to comment about starting this way. What's the drawbacks of
>>starting with Lisp, if any? What are the advantages? What's the time
>>factor
>>in getting up and running and doing practical, useful things with it
>>versus
>>the time factor for other languages? I cannot tell you exactly where I
>>want
>>to go with it; I'm too new to the whole thing. I can tell you that I'm
>>going
>>to graduate soon with a CS degree and I can't program. I can tell you that
>>I
>>want to work with databases for a competitive edge in a business I want to
>>start in healthcare that can branch out in many different directions, from
>>home health to community outreach.
>>
>>I'm lost.
>>
>>Why Lisp?
>>
>
> If you think about working in so called Information Technology,
> don't waste your time learning Lisp. Nobody, repeat, NOBODY in the
> industry is using Lisp except the fanatics on this group. However,
> these guys will not hire you and will not pay your bills.
>
> Learn Java, especially J2EE, what becomes the dominating platform in
> the industry. Don't learn C++, its future is past. Learn C# and .NET
> platform. It is more and more popular within the industry. Learn SQL
> if you want to work with databases.
>
> A.L.
Although I would agree that J2EE is a dominating platform in the industry
and seems to be a language that you have to get to know, I don't believe
that learning Lisp is an exercise in futility nor do I see posters in this
group as fanatics. I've learned that it's not always the best choice to put
all your eggs in baskets that are ubiquitous. There are advantages but there
are also disadvantages. For example, I did some drafting for an architect
for about a year and he used a specialized program called ArchiCAD on Macs
instead of the ubiquitous AutoCAD on Windows. After working with both I can
tell you that ArchiCAD was by far the better program for architects.
AutoCAD's Architectural Desktop attempted to copy some concepts from
ArchiCAD but there's was still no comparison. I was able to create working
set of plans in ArchiCAD in about 2/3 to 1/2 half the time it took me using
AutoCAD. Yet those using ArchiCAD in my area are rare. Even so, today I
would have no problem landing a job, for higher pay, using ArchiCAD due to
the very fact that those with the skill set are NOT ubiquitous. Some of the
most productive architects out there, those who "know", use it. AutoCAD was
something I had to know to be able to work with others in the industry and
to access the many resources based on its platform but it was not the best
choice... not if you wanted a competitive edge in the architectural
industry. I suspect the same may be true when considering Java vs. Lisp.
Java is ubiquitous and you have to know it but Lisp could be the edge.
> a specialized program called ArchiCAD on Macs
> instead of the ubiquitous AutoCAD on Windows. After working
> with both I can tell you that ArchiCAD was by far the better program
Is there anything comparable in open source for Linux/FreeBSD/etc.?
A.L. wrote:
> If you think about working in so called Information Technology,
> don't waste your time learning Lisp. Nobody, repeat, NOBODY in the
> industry is using Lisp except the fanatics on this group.
You learn only things you will be using?
It is not a good idea in general. Alternative programming languages
worth
learning at least because they could be the source for good ideas on
how
to use your SuperHyperMegaPopular-bloated-shit language efficiently.