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Frequently Asked Questions (FAQS);faqs.351
ANSWER: You have an old version of Emacs compiled before GCC 2.11c and
you are using the Linux extended filesystem. Get the new version.
QUESTION: Why doesn't Control-Z doesn't work right with Emacs?
QUESTION: Why doesn't job control work in shell mode?
ANSWER: You have a really old version of Linux Emacs. Get the new one.
===================8<==========>8================
--
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# LaBRI | #
# 351 cours de la Liberation | e-mail: corsini@labri.greco-prog.fr #
# 33405 Talence Cedex | #
# | #
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
--
There will be some sig, once our local net will be reliable.
Right now I rather stay anonymous.
Xref: bloom-picayune.mit.edu comp.lang.lisp:8749 news.answers:4559
Path: bloom-picayune.mit.edu!enterpoop.mit.edu!spool.mu.edu!uunet!ogicse!das-news.harvard.edu!cantaloupe.srv.cs.cmu.edu!crabapple.srv.cs.cmu.edu!mkant
From: mkant+@cs.cmu.edu (Mark Kantrowitz)
Newsgroups: comp.lang.lisp,news.answers
Subject: FAQ: Lisp Frequently Asked Questions 1/6 [Monthly posting]
Summary: Introductory Matter and Bibliography of Introductions and References
Message-ID: <lisp-faq-1.text_724237235@cs.cmu.edu>
Date: 13 Dec 92 09:01:07 GMT
Article-I.D.: cs.lisp-faq-1.text_724237235
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Archive-name: lisp-faq/part1
Last-Modified: Thu Nov 5 19:30:40 1992 by Mark Kantrowitz
Version: 1.27
;;; ****************************************************************
;;; Answers to Frequently Asked Questions about Lisp ***************
;;; ****************************************************************
;;; Written by Mark Kantrowitz and Barry Margolin
;;; lisp-faq-1.text -- 60654 bytes
This post contains Part 1 of the Lisp FAQ.
If you think of questions that are appropriate for this FAQ, or would
like to improve an answer, please send email to us at lisp-faq@think.com.
Note that the lisp-faq mailing list is for discussion of the content
of the FAQ posting only. It is not the place to ask questions about Lisp;
use either the common-lisp@ai.sri.com mailing list or the
comp.lang.lisp newsgroup for that. If a question appears frequently
in one of those forums, it will get added to the FAQ list.
There are currently six parts to the Lisp FAQ:
1. Introductory Matter and Bibliography of Introductions and References
2. General Questions
3. Common Programming Pitfalls
4. Lisp/Scheme Implementations and Mailing Lists
5. CLOS and PCL Questions
6. FTP Archives and Resources
All parts are posted to comp.lang.lisp. Part 4 is cross-posted to the
comp.lang.scheme newsgroup. Part 5 is cross-posted to the
comp.lang.clos newsgroup.
Topics Covered (Part 1):
[1-0] What is the purpose of this newsgroup?
[1-1] What documentation is available on Lisp? How can I learn Lisp?
[1-2] How can I improve my Lisp programming style and coding efficiency?
[1-3] Where can I learn about implementing Lisp interpreters and compilers?
[1-4] What does CLOS, PCL, X3J13, CAR, CDR, ... mean?
[1-5] Where can I get a copy of the draft ANSI standard for Common Lisp?
[1-6] Lisp Job Postings
Topics Covered (Part 2):
[2-1] Is there a GNU-Emacs interface to Lisp?
[2-3] What is the equivalent of EXPLODE and IMPLODE in Common Lisp?
[2-4] Is Lisp inherently slower than more conventional languages such as C?
[2-5] Why does Common Lisp have "#'"?
[2-6] How do I call non-Lisp functions from Lisp?
[2-7] Can I call Lisp functions from other languages?
[2-8] I want to call a function in a package that might not exist at
compile time. How do I do this?
[2-9] What is CDR-coding?
[2-10] What is garbage collection?
[2-11] How do I save an executable image of my loaded Lisp system?
How do I run a Unix command in my Lisp?
How do I get the current directory name from within a Lisp program?
[2-12] I'm porting some code from a Symbolics Lisp machine to some
other platform, and there are strange characters in the code.
What do they mean?
[2-13] History: Where did Lisp come from?
[2-14] How do I find the argument list of a function?
How do I get the function name from a function object?
[2-15] How can I have two Lisp processes communicate via unix sockets?
Common Pitfalls (Part 3):
[3-0] Why does (READ-FROM-STRING "foobar" :START 3) return FOOBAR
instead of BAR?
[3-1] Why can't it deduce from (READ-FROM-STRING "foobar" :START 3)
that the intent is to specify the START keyword parameter
rather than the EOF-ERROR-P and EOF-VALUE optional parameters?
[3-2] Why can't I apply #'AND and #'OR?
[3-3] I used a destructive function (e.g. DELETE, SORT), but it
didn't seem to work. Why?
[3-4] After I NREVERSE a list, it's only one element long. After I
SORT a list, it's missing things. What happened?
[3-5] Why does (READ-LINE) return "" immediately instead of waiting
for me to type a line?
[3-6] I typed a form to the read-eval-print loop, but nothing happened. Why?
[3-7] DEFMACRO doesn't seem to work.
When I compile my file, LISP warns me that my macros are undefined
functions, or complains "Attempt to call <function> which is
defined as a macro.
[3-8] Name conflict errors are driving me crazy! (EXPORT, packages)
[3-9] Closures don't seem to work properly when referring to the
iteration variable in DOLIST, DOTIMES and DO.
[3-10] What is the difference between FUNCALL and APPLY?
[3-11] Miscellaneous things to consider when debugging code.
[3-12] When is it right to use EVAL?
[3-13] Why does my program's behavior change each time I use it?
[3-14] When producing formatted output in Lisp, where should you put the
newlines (e.g., before or after the line, FRESH-LINE vs TERPRI,
~& vs ~% in FORMAT)?
[3-15] I'm using DO to do some iteration, but it doesn't terminate.
Lisp/Scheme Implementations and Mailing Lists (Part 4):
[4-0] Free Lisp implementations.
[4-1] Commercial Lisp implementations.
[4-2] Free Scheme implementations.
[4-3] Commercial Scheme implementations.
[4-4] Other Commercial Lisp-like Language implementations.
[4-5] Where can I get an implementation of Prolog in Lisp?
[4-6] What is Dylan?
[4-7] What Lisp-related discussion groups and mailing lists exist?
[4-8] What are R4RS and IEEE P1178?
[4-9] How do I do object-oriented programming in Scheme?
CLOS Questions (Part 5):
[5-0] What is CLOS (PCL) and where can I get it?
How do you pronounce CLOS?
[5-1] What documentation is available about object-oriented
programming in Lisp?
[5-2] How I write a function that can access defstruct slots by
name? I would like to write something like
(STRUCTURE-SLOT <object> '<slot-name>).
[5-3] How can I list all the CLOS instances in a class?
[5-4] How can I store data and CLOS instances (with possibly circular
references) on disk so that they may be retrieved at some later
time?
[5-5] Given the name of a class, how can I get the names of its slots?
FTP Resources (Part 6):
[6-0] General information about FTP Resources for Lisp and Scheme
[6-1] Repositories of Lisp Software
[6-2] Repositories of Scheme Software
[6-3] Publicly Redistributable Lisp Software
[6-4] Publicly Redistributable Scheme Software
[6-5] How can I use the X Window System or other GUIs from Lisp?
[6-6] Formatting code in LaTeX
Search for [#] to get to question number # quickly.
Introduction:
Certain questions and topics come up frequently in the various network
discussion groups devoted to and related to Lisp. This file/article is
an attempt to gather these questions and their answers into a convenient
reference for Lisp programmers. It (or a reference to it) is posted
periodically. The hope is that this will cut down on the user time and
network bandwidth used to post, read and respond to the same questions
over and over, as well as providing education by answering questions
some readers may not even have thought to ask.
This is not a Lisp tutorial, nor is it an exhaustive list of all Lisp
intricacies. Lisp is a very powerful and expressive language, but with
that power comes many complexities. This list attempts to address the
ones that average Lisp programmers are likely to encounter. If you are
new to Lisp, see the answer to the question "How can I learn Lisp?".
The latest version of this file is available via anonymous FTP from CMU
and Thinking Machines:
To obtain the files from CMU, connect by anonymous ftp to any CMU CS
machine (e.g., ftp.cs.cmu.edu [128.2.206.173]), using username
"anonymous" and password "name@host". The files lisp-faq-1.text,
lisp-faq-2.text, lisp-faq-3.text, lisp-faq-4.text, lisp-faq-5.text
and lisp-faq-6.text are located in the directory
/afs/cs.cmu.edu/user/mkant/Public/Lisp-Utilities/
[Note: You must cd to this directory in one atomic operation, as
some of the superior directories on the path are protected from
access by anonymous ftp.] If your site runs the Andrew File System,
you can just cp the files directly without bothering with FTP.
To obtain the files from Thinking Machines, ftp them from ftp.think.com,
in the directory /public/think/lisp/. The file faq.text contains all the
parts of the FAQ in one file. In addition, specific versions of the FAQ
are available as faq-<version>.text.
Unless otherwise specified, the Lisp dialect referred to is Common Lisp,
as defined by "Common Lisp: the Language" (aka "CLtL1") as well as
corrections (but not enhancements) from "Common Lisp: the Language, 2nd
Edition" (aka "CLtL2"), both by Guy L. Steele, Jr. and published by
Digital Press. Note that CLtL2 is NOT an official specification for
the language; ANSI Committee X3J13 is preparing such a specification.
See question [1-5] for information on the status of the ANSI
specification for Common Lisp. Enhancements such as CLOS, conditions,
and the LOOP macro will be referred to separately.
----------------------------------------------------------------
[1-0] What is the purpose of this newsgroup?
The newsgroup comp.lang.lisp exists for general discussion of
topics related to the programming language Lisp. For example, possible
topics can include (but are not necessarily limited to):
announcements of Lisp books and products
discussion of programs and utilities written in Lisp
discussion of portability issues
questions about possible bugs in Lisp implementations
problems porting an implementation to some architecture
Postings should be of general interest to the Lisp community. See also
question [4-7].
Questions about object oriented programming in Lisp should be directed
to the newsgroup comp.lang.clos. Similarly, questions about the
programming language Scheme should be directed to the newsgroup
comp.lang.scheme. Discussion of functional programming language issues
should be directed to the newsgroup comp.lang.functional. Discussion
of AI programs implemented in Lisp should sometimes be cross-posted to
the newsgroup comp.ai.
----------------------------------------------------------------
[1-1] What documentation is available on Lisp?
How can I learn Lisp?
There are several good Lisp introductions and tutorials:
1. David S. Touretzky
"Common Lisp: A Gentle Introduction to Symbolic Computation"
Benjamin/Cummings Publishers, 1990. 384 pages.
Perhaps the best tutorial introduction to the language. It has
clear and correct explanations, and covers some fairly advanced
topics. The book is an updated Common Lisp version of the 1984
edition published by Harper and Row Publishers.
Three free Lisp educational tools which were used in the book --
Evaltrace, DTRACE and SDRAW -- are available by anonymous ftp from
b.gp.cs.cmu.edu:/usr/dst/public/{lisp,evaltrace}. Evaltrace is a
graphical notation for explaining how evaluation works and is
described in "Visualizing Evaluation in Applicative Languages" by
David S. Touretzky and Peter Lee, CACM 45-59, October 1992. DTRACE
is a "detailed trace" which provides more information than the
tracing tools provided with most Common Lisp implementations. SDRAW
is a program that draws cons cell structures both for X11 and ascii
terminals.
2. Robert Wilensky
"Common LISPcraft"
W. W. Norton, 1986. 385 pages.
3. Wade L. Hennessey
"Common Lisp"
McGraw-Hill, 1989. 395 pages.
Fairly good, but jumps back and forth from the simple to the
complex rather quickly, with no clear progression in difficulty.
4. Laurent Siklossy
"Let's Talk LISP"
Prentice-Hall, NJ, 1976. 237 pages.
Good introduction, but quite out of date.
5. Stuart C. Shapiro
"Common Lisp: An Interactive Approach"
Computer Science Press/W.H. Freeman, New York, 1992.
ISBN 0-7167-8218-9
Other introductions to Lisp include:
1. A. A. Berk.
"LISP, The Language of Artificial Intelligence"
Van Nostrand Reinhold, 1985. 160 pages.
2. Paul Y. Gloess.
"An Alfred handy guide to Understanding LISP"
Alfred Publishers (Sherman Oaks, CA), 1982. 64 pages.
3. Ward D. Maurer.
"The Programmer's Introduction to LISP"
American Elsevier, 1972. 112 pages.
4. Hank Bromley and Richard Lamson.
"LISP Lore: A Guide to Programming the LISP Machine"
Kluwer Academic (Boston), 1987. 337 pages.
5. Sharam Hekmatpour.
"Introduction to LISP and Symbol Manipulation"
Prentice Hall (New York), 1988. 303 pages.
6. Deborah G. Tatar
"A programmer's guide to Common Lisp"
Digital Press, 1987. 327 pages. ISBN 0-932376-87-8.
Good introduction on Common Lisp.
7. Timothy Koschmann
"The Common Lisp Companion"
John Wiley & Sons, 1990.
Targeted for those with some programming experience who wish to
learn draft-ANSI Common Lisp, including CLOS and the CL condition
system. Examples progress incrementally from simple numerical
calculation all the way to a logic-programming extension to CL.
More advanced introductions to Lisp and its use in Artificial
Intelligence include:
1. Peter Norvig.
"Paradigms of AI Programming: Case Studies in Common Lisp"
Morgan Kaufmann, 1992. 946 pages. ISBN 1-55860-191-0.
Provides an in-depth exposition of advanced AI programming techniques
and includes large-scale detailed examples. The book is the most
advanced AI/Common-Lisp programming text and reference currently
available, and hence is not for the complete novice. It focuses on the
programming techniques necessary for building large AI systems,
including object-oriented programming, and has a strong performance
orientation.
The text is marked by its use of "non-toy" examples to illustrate the
techniques. All of the examples are written in Common Lisp, and copies
of the source code are available by anonymous ftp from
unix.sri.com:pub/norvig and on disk in Macintosh or DOS format from
the publisher. Some of the techniques described include rule-based
pattern matching (GPS, Eliza, a subset of Macsyma, the Emycin expert
system shell), constraint propagation and backtracking (Waltz
line-labelling), alpha-beta search (Othello), natural language
processing (top-down, bottom-up and chart parsing), logic-programming
(unification and Prolog), interpreters and compilers for Scheme, and
object-oriented programming (CLOS).
The examples are also used to illustrate good programming style and
efficiency. There is a guide to trouble-shooting and debugging Lisp
programs, a style guide, and a discussion of portability problems.
Some of the efficiency techniques described include memoization,
data indexing, compilation, delaying computation, proper use of
declarations, avoiding garbage collection, and choosing and using the
correct data structure.
The book also serves as an advanced introduction to Common Lisp, with
sections on the Loop macro, CLOS and sequences, and some coverage of
error handling, series, and the package facility.
2. Eugene Charniak, Christopher K. Riesbeck, Drew V. McDermott
and James R. Meehan.
"Artificial Intelligence Programming", 2nd edition.
Lawrence Erlbaum Associates (Hillsdale, NJ), 1987. 533 pages.
Provides many nice code fragments, all of which are written
in Common Lisp. The first half of the book covers topics
like macros, the reader, data structures, control structures,
and defstructs. The second half of the book describes
programming techniques specific to AI, such as
discrimination nets, production systems, deductive database
retrieval, logic programming, and truth maintenance.
3. Patrick H. Winston and Berthold K. P. Horn.
"LISP", 3rd edition.
Addison-Wesley (Reading, MA), 1989. 611 pages. ISBN 0-201-08319-1
Covers the basic concepts of the language, but also gives a lot
of detail about programming AI topics such as rule-based expert
systems, forward chaining, interpreting transition trees,
compiling transition trees and finding patterns in images. Not
a tutorial. Has many good examples.
4. Rodney A. Brooks.
"Programming in Common Lisp"
Wiley, 1985. 303 pages.
5. John R. Anderson, Albert T. Corbett, and Brian J. Reiser.
"Essential LISP"
Addison-Wesley (Reading, MA), 1987. 352 pages.
Concentrates on how to use Lisp with iteration and recursion.
6. Robert D. Cameron and Anthony H. Dixon
"Symbolic Computing with Lisp"
Prentice-Hall, 1992, 326 pages. ISBN 0-13-877846-9.
The book is intended primarily as a third-year computer science
text. In terms of programming techniques, it emphasizes recursion
and induction, data abstraction, grammar-based definition of Lisp
data structures and functional programming style. It uses
two Lisp languages:
(1) a purely functional subset of Lisp called Small Lisp and
(2) Common Lisp.
An MS-DOS interpreter for Small Lisp (including source) is
provided with the book. It considers applications of Lisp
to formal symbolic data domains: algebraic expressions,
logical formulas, grammars and programming languages.
7. Hasemer and Domingue.
"Common Lisp Programming for Artificial Intelligence"
Addison-Wesley, 1989.
8. Steven Tanimoto
"The Elements of Artificial Intelligence: An Introduction Using Lisp"
Computer Science Press, Rockville, MD, 1987, 530 pages.
9. Patrick R. Harrison
"Common Lisp and Artificial Intelligence"
Prentice Hall, 1990. ISBN 0-13-155243
10. Rajeev Sangal
"Programming Paradigms in Lisp"
McGraw-Hill, 1991. ISBN 0-07-054666-5.
General Lisp reference books include:
1. Guy L. Steele
"Common Lisp: The Language" [CLtL1]
Digital Press, 1984. 465 pages. ISBN 0-932376-41-X.
2. Guy L. Steele
"Common Lisp: The Language, 2nd Edition" [CLtL2]
Digital Press, 1990. 1029 pages. ISBN 1-55558-041-6.
3. Franz Inc.
"Common Lisp: The Reference"
Addison-Wesley, Reading, MA 1988. ISBN 0-201-11458-5
Entries on lisp functions in alphabetical order.
4. K. Dybvig.
"The Scheme programming language"
Prentice Hall, 1987.
Good reference for Scheme.
Lisp periodicals include:
1. LISP Pointers.
Published by ACM SIGPLAN six times a year. Volume 1, Number 1
was April-May 1987.
2. LISP and Symbolic Computation, Kluwer Academic Press. Volume 1
was published in 1989. (jlz@lucid.com is the editor). ISSN 0892-4635.
Subscriptions: Institutions $169; Individuals $80. Add $8 for
air mail. Kluwer Academic Publishers, PO Box 322, 3300 AH Dordrecht,
The Netherlands, or Kluwer Academic Publishers, PO Box 358, Accord
Station, Hingham, MA 02018-0358.
3. Proceedings of the biannual ACM Lisp and Functional Programming
Conference. (First one was in 1980.)
4. Proceedings of the annual Lisp Users and Vendors Conference.
Implementation-specific questions:
1. Lucid. See the wizards.doc file that comes with the Lucid
release. It describes functions, macros, variables and constants that
are not official parts of the product and are not supported.
Constructs described in this file include: the interrupt facility, the
source file recording facility, the resource facility, multitasking,
writing your own streams, lisp pipes, i/o buffers, the compiler,
floating-point functions, memory management, debugger information, the
window tool kit, extensions to the editor, the foreign function
interface, clos information, delivery toolkit information, and Lucid
lisp training classes. The wizards.doc file also covers i/o
constructs, functions for dealing with DEFSTRUCT, functions and
constants for dealing with procedure objects, functions and constants
for dealing with code objects, function for mapping objects,
additional keyword argument to DISKSAVE, function used in the
implementation of arrays, function for monitor-specific behavior for a
process, additional keyword argument to RUN-PROGRAM, and load-time
evaluation.
Introductions to Scheme (Many books on Scheme are worth reading
even if you use Common Lisp, because many of the issues are similar):
1. Harold Abelson and Gerald Jay Sussman, with Julie Sussman.
"Structure and Interpretation of Computer Programs"
MIT Press (Cambridge, MA) and McGraw-Hill (New York), 1985.
542 pages. ISBN 0-262-01077-1
Starts off introductory, but rapidly gets into powerful
Lisp-particular constructs, such as using closures and
engines, building interpreters, compilers and
object-oriented systems.
2. Daniel P. Friedman and M. Felleisen.
"The Little LISPer"
MIT Press (Cambridge, MA), 3rd printing, 1989. ISBN 0-262-56038-0.
Science Research Associates (Chicago), 3rd ed, 1989. 206 pages.
Good for a quick introduction. Uses Scheme instead of
Common Lisp. (The book uses a dialect of Scheme with
footnotes about translating to Scheme or Common Lisp. The
footnotes won't allow a non-expert to use Common Lisp for
the advanced chapters because of the complexity.)
3. George Springer and Daniel P. Friedman
"Scheme and the Art of Programming"
MIT Press and McGraw Hill, 1990, 596 pages.
Introduces basic concepts of programming in Scheme. Also deals
with object oriented programming, co-routining, continuations.
Gives numerous examples.
4. Wolfgang Kreutzer and Bruce McKenzie
"Programming for Artificial Intelligence:
Methods, Tools and Applications"
Addison-Wesley (Reading, MA), 1990. 682 pages.
ISBN 0-201-41621-2.
Discusses Scheme, Prolog, and Smalltalk, gives an overview of
the history and philosophy of AI, surveys three major
programming paradigms (procedural, declarative, and
object-oriented), and metaphors to AI programming.
5. Smith
"Introduction to Scheme"
1988.
Focuses on PC Scheme.
6. Michael Eisenberg
"Programming in Scheme"
Scientific Press (Redwood City, CA), 1988. 304 pages.
7. The Ken Dickey article, "The Scheme Programming Language", in
COMPUTER LANGUAGES magazine, and the Revised^4 Report on the
Algorithmic Language Scheme, both of which are available by anonymous
ftp from the scheme archive at nexus.yorku.ca.
8. Two articles in BYTE Magazine, February 1988, by Abelson and
Sussman, and Clinger.
9. The Info files from the MIT Scheme implementation.
Special Topics:
Garbage Collection:
Wilson, Paul R., "Uniprocessor Garbage Collection Techniques"
Proceedings of the 1992 International Workshop on Memory Management.
Surveys garbage collection techniques. Available by anonymous ftp from
cs.utexas.edu:pub/garbage/gcsurvey.ps. Contact wilson@cs.utexas.edu
for more info.
----------------------------------------------------------------
[1-2] How can I improve my Lisp programming style and coding efficiency?
There are several books about Lisp programming style, including:
1. Molly M. Miller and Eric Benson
"Lisp Style and Design"
Digital Press, 1990. 214 pages. ISBN 1-55558-044-0.
How to write large Lisp programs and improve Lisp programming
style. Uses the development of Lucid CL as an example.
2. Robin Jones, Clive Maynard, and Ian Stewart.
"The Art of Lisp Programming"
Springer-Verlag, 1989. 169 pages.
3. W. Richard Stark.
"LISP, Lore, and Logic: an algebraic view of LISP
programming, foundations, and applications"
Springer-Verlag, 1990. 278 pages. ISBN 0-387-97072-X
Self-modifying code, self-reproducing programs, etc.
4. CMU CL User's Manual, Chapter 7, (talks about writing
efficient code). It is available by anonymous ftp from any CMU CS
machine (e.g., ftp.cs.cmu.edu [128.2.206.173]) as the file
/afs/cs.cmu.edu/project/clisp/docs/cmu-user/cmu-user.ps
[when getting this file by anonymous ftp, one must cd to
the directory in one atomic operation, as some of the superior
directories on the path are protected from access by anonymous ftp.]
5. See also Norvig's book, SICP (Abelson & Sussman), SAP
(Springer and Friedman).
6. Hallvard Tretteberg's Lisp Style Guide is available by anonymous
ftp in ftp.think.com:/public/think/lisp/style-guide.text. There is
a fair bit of overlap between Hallvard's style guide and the notes
below and in part 3 of this FAQ.
Here are some general suggestions/notes about improving Lisp
programming style, readability, correctness and efficiency:
General Programming Style Rules:
- Write short functions, where each function provides a single,
well-defined operation. Small functions are easier to
read, write, test, debug, and understand.
- Use descriptive variable and function names. If it isn't clear
from the name of a function or variable what its purpose is,
document it with a documentation string and a comment. In fact,
even if the purpose is evident from the name, it is still worth
documenting your code.
- Don't write Pascal (or C) code in Lisp. Use the appropriate
predefined functions -- look in the index to CLtL2, or use the
APROPOS and DESCRIBE functions. Don't put a close parenthesis
on a line by itself -- this can really aggravate programmers
who grew up on Lisp. Lisp-oriented text editors include tools
for ensuring balanced parentheses and for moving across
pairs of balanced parentheses.
- Use proper indentation -- you should be able to understand
the structure of your definitions without noticing the parentheses.
The following functions often abused or misunderstood by novices.
Think twice before using any of these functions.
- EVAL. Novices almost always misuse EVAL. When experts use
EVAL, they often would be better off using APPLY, FUNCALL, or
SYMBOL-VALUE. Use of EVAL when defining a macro should set off
a warning bell -- macro definitions are already evaluated
during expansion. See also the answer to question 3-12.