[30046] in Perl-Users-Digest
Perl-Users Digest, Issue: 1289 Volume: 11
daemon@ATHENA.MIT.EDU (Perl-Users Digest)
Tue Feb 19 09:09:40 2008
Date: Tue, 19 Feb 2008 06:09:05 -0800 (PST)
From: Perl-Users Digest <Perl-Users-Request@ruby.OCE.ORST.EDU>
To: Perl-Users@ruby.OCE.ORST.EDU (Perl-Users Digest)
Perl-Users Digest Tue, 19 Feb 2008 Volume: 11 Number: 1289
Today's topics:
A case with Combinations in Sets <anirbid.banerjee@gmail.com>
Re: bash and perl <jurgenex@hotmail.com>
Re: Linux, IO::Socket::INET and recv'ing broadcasted UD <ben@morrow.me.uk>
new CPAN modules on Tue Feb 19 2008 (Randal Schwartz)
Re: Number of days since 1/1/2000 (Randal L. Schwartz)
Posting Guidelines for comp.lang.perl.misc ($Revision: tadmc@seesig.invalid
Re: Regular Expression to Replace UPPER Case Text with <cwilbur@chromatico.net>
Re: Regular Expression to Replace UPPER Case Text with <cartercc@gmail.com>
Re: Why `for local $var (LIST) ...' not allowed? <achimpeters@gmx.de>
Digest Administrivia (Last modified: 6 Apr 01) (Perl-Users-Digest Admin)
----------------------------------------------------------------------
Date: Tue, 19 Feb 2008 01:26:40 -0800 (PST)
From: "anirbid.banerjee@gmail.com" <anirbid.banerjee@gmail.com>
Subject: A case with Combinations in Sets
Message-Id: <363cf096-80c9-49b4-b3c7-efc65946bb52@d4g2000prg.googlegroups.com>
Hi,
I have two Sets A and B with N DISTINCT elements each. Both A and B
are related to each other so that B contains complement of A. For eg.A
= {a, b, c} , B = {a*, b* c*}. I would need a perl script to generate
all possible combinations between A and B satisfying the following
conditions:
a) The number of elements in the Combined set n(C) = N.
b) None of the combination should contain both an element and its
complement : i.e. {a, a*, b}, {b,c, c*} are invalid combinations.
c) There should be exactly 2^N combinations.
Regards,
Anirbid
------------------------------
Date: Tue, 19 Feb 2008 11:25:09 GMT
From: Jürgen Exner <jurgenex@hotmail.com>
Subject: Re: bash and perl
Message-Id: <bpelr3hn9h386ccp2dsb13h163co4e9ift@4ax.com>
David Williams <dw149@acmex.gatech.edu> wrote:
>I don't think my first message went through.
>Wondering if there is a way to mix perl and shell scripts?
No problem.
>Like this:
> #!/usr/bin/perl
>[...]
> #!/bin/bash
>[...]
>I tried this above but Perl did not like it.
Well, no, you cannot all of a sudden change the programming language in the
middle of a program.
Of course you can always just call a bash script from the Perl script and
vice versa. Or you can rewrite your bash code in Perl. I don't think there
is anything you can do in bash that you couldn't do in Perl, even as a
practical matter, not just theoretical Turing Completeness.
jue
------------------------------
Date: Tue, 19 Feb 2008 06:11:47 +0000
From: Ben Morrow <ben@morrow.me.uk>
Subject: Re: Linux, IO::Socket::INET and recv'ing broadcasted UDP
Message-Id: <3i8q85-rs82.ln1@osiris.mauzo.dyndns.org>
Quoth DJ Stunks <DJStunks@gmail.com>:
> On Feb 18, 4:42 pm, Ben Morrow <b...@morrow.me.uk> wrote:
> > Quoth DJ Stunks <DJStu...@gmail.com>:
> >
> > > The DHCPOFFER is broadcasted regardless (Ethernet
> > > destination MAC = ff:ff:ff:ff:ff:ff; destination IP = 255.255.255.255;
> > > destination udp port = 68) but my socket never receives it.
> >
> > That's... odd. Can you recieve other broadcast datagrams?
> >
> > Have you tried using a PF_PACKET socket?
>
> I thought it was odd too, but I'm continuing to research (so
> frustrated! ;-)) and I think what I'm finding is that it's not that
> odd...
>
> Here's a post from Solaris' bug tracker:
> http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4191980.
> The originator had a similar problem, but with Java. The response
> was:
>
> "The Solaris (& Linux for that matter) behavior is that to be able to
> receive broadcasts a UDP socket has to be bound to the wildcard
> address (aka anylocal). This has been the defacto standard behavior
> since the days of BSD 4.3. Win32 behaviors differs from that. So the
> only way to be guaranteed to receive the broadcasts on any platform is
> to bind to the wildcard address."
OK. I didn't know that, but it makes some sense.
> So I tried changing my IO::Socket::INET constructor to use INADDR_ANY,
> but no luck. The constructor seems to ignore PeerAddr => '0.0.0.0';
No, you need LocalAddr => '0.0.0.0'. It's the address of *this* socket
you're setting, not the address you're talking to. For UDP sockets,
PeerAddr sets the default destination for sends.
> This page (http://wiki.forum.nokia.com/index.php/
> How_to_use_udp_broadcast) shows how to set up a Python socket for UDP
> broadcast.
Whoa... that page is about PyS60, otherwise known as 'Python for itty
bitty Symbian phones with rather weird network stacks' :). However, the
code they give is basically the same as on any other platform; here
(FreeBSD) I can send and recieve broadcast datagrams with
#!/usr/bin/perl -l
use warnings;
use strict;
use IO::Socket::INET;
use Data::Dump qw/dump/;
my $port = 8091;
if ($ARGV[0] eq 'recv') {
my $SCK = IO::Socket::INET->new(
Type => SOCK_DGRAM,
Proto => 'udp',
LocalAddr => '0.0.0.0',
LocalPort => $port,
Broadcast => 1,
) or die "socket: $@";
$SCK->recv(my $buf, 512, 0)
or die "recv: $@ $!";
print dump $buf;
}
else {
my $SCK = IO::Socket::INET->new(
Type => SOCK_DGRAM,
Proto => 'udp',
PeerAddr => $ARGV[1],
PeerPort => $port,
Broadcast => 1,
) or die "socket: $!";
my $buf = 'Hello world!';
$SCK->send($buf)
or die "send: $!";
}
__END__
though I find I have to send to 192.168.1.255 (the local net broadcast
addr) rather than 255.255.255.255, which ought to be the same. I don't
know why that is.
> So now my question is, how do I set up a Perl socket similarly? Can I
> still use IO::Socket::INET to set PF_INET (is that the same as
> PF_PACKET?) or do I have to use Socket instead?
No, PF_PACKET isn't the same as PF_INET. PF_INET is the normal Internet
protocol family: basically TCP or UDP over IP, though on most OSen you
can use PF_INET/SOCK_RAW sockets to talk any IP protocol, including
ICMP. In Perl you can use IO::Socket::INET to do anything your OS will
let you do with PF_INET sockets.
PF_PACKET is a Linux-specific protocol family for talking directly to
the network driver; it allows you to send and receive raw Ethernet
frames, for example. Perl has no IO::Socket support for PF_PACKET
(though writing an IO::Socket::PACKET wouldn't be too hard: it's mostly
just packing and unpacking the addresses, which is code you'd need to
write to use these sockets anyway), so if you need these you would have
to use the socket builtins (Socket wouldn't help, here, as that only has
AF_INET/AF_UNIX support).
Ben
------------------------------
Date: Tue, 19 Feb 2008 05:42:16 GMT
From: merlyn@stonehenge.com (Randal Schwartz)
Subject: new CPAN modules on Tue Feb 19 2008
Message-Id: <JwH16G.r2A@zorch.sf-bay.org>
The following modules have recently been added to or updated in the
Comprehensive Perl Archive Network (CPAN). You can install them using the
instructions in the 'perlmodinstall' page included with your Perl
distribution.
Algorithm-TokenBucket-0.3
http://search.cpan.org/~kappa/Algorithm-TokenBucket-0.3/
Token bucket rate limiting algorithm
----
ApacheLog-Parser-v0.0.1
http://search.cpan.org/~ewilhelm/ApacheLog-Parser-v0.0.1/
parse apache 'combined' log format
----
Bundle-Thread-1.02
http://search.cpan.org/~jdhedden/Bundle-Thread-1.02/
A bundle of modules for supporting threads in Perl
----
Catalyst-Controller-Atompub-0.3.4
http://search.cpan.org/~takeru/Catalyst-Controller-Atompub-0.3.4/
A Catalyst controller for the Atom Publishing Protocol
----
Catalyst-Model-ISBNDB-0.21
http://search.cpan.org/~rjray/Catalyst-Model-ISBNDB-0.21/
Provide Catalyst access to isbndb.com
----
Class-Accessor-Classy-v0.9.0
http://search.cpan.org/~ewilhelm/Class-Accessor-Classy-v0.9.0/
accessors with minimal inheritance
----
Config-IniHash-3.00.00
http://search.cpan.org/~jenda/Config-IniHash-3.00.00/
Perl extension for reading and writing INI files
----
Config-Validate-0.2.6
http://search.cpan.org/~cmo/Config-Validate-0.2.6/
Validate data structures generated from configuration files. (Or anywhere else)
----
Crypt-OpenSSL-CA-0.17
http://search.cpan.org/~domq/Crypt-OpenSSL-CA-0.17/
The crypto parts of an X509v3 Certification Authority
----
Crypt-SSLeay-0.57_01
http://search.cpan.org/~dland/Crypt-SSLeay-0.57_01/
OpenSSL support for LWP
----
DBD-Pg-2.0.1_3
http://search.cpan.org/~turnstep/DBD-Pg-2.0.1_3/
PostgreSQL database driver for the DBI module
----
DBD-Pg-2.1.0
http://search.cpan.org/~turnstep/DBD-Pg-2.1.0/
PostgreSQL database driver for the DBI module
----
Data-Consumer-0.09
http://search.cpan.org/~yves/Data-Consumer-0.09/
Repeatedly consume a data resource in a robust way
----
Data-SExpression-0.35
http://search.cpan.org/~nelhage/Data-SExpression-0.35/
Parse Lisp S-Expressions into perl data structures.
----
Data-Validate-Domain-0.09
http://search.cpan.org/~neely/Data-Validate-Domain-0.09/
domain validation methods
----
Debian-Package-Make-0.02
http://search.cpan.org/~hbengen/Debian-Package-Make-0.02/
Perl extension for autobuilding Debian packages
----
Devel-Fail-MakefilePL-1.011
http://search.cpan.org/~mthurn/Devel-Fail-MakefilePL-1.011/
a distro that always fails the `perl Makefile.PL` stage
----
File-Fu-v0.0.1
http://search.cpan.org/~ewilhelm/File-Fu-v0.0.1/
file and directory objects
----
Games-Roshambo-1.01
http://search.cpan.org/~cthom/Games-Roshambo-1.01/
Perl OO Rock/Paper/Scissors
----
Hyper-Developer-0.06
http://search.cpan.org/~acid/Hyper-Developer-0.06/
Hyper Developer Tools
----
Hyper-Developer-0.07
http://search.cpan.org/~acid/Hyper-Developer-0.07/
Hyper Developer Tools
----
IO-Lambda-0.10
http://search.cpan.org/~karasik/IO-Lambda-0.10/
non-blocking I/O in lambda style
----
Image-Size-3.1.1
http://search.cpan.org/~rjray/Image-Size-3.1.1/
read the dimensions of an image in several popular formats
----
LEOCHARRE-Dev-1.04
http://search.cpan.org/~leocharre/LEOCHARRE-Dev-1.04/
----
Lingua-Translit-0.02
http://search.cpan.org/~alinke/Lingua-Translit-0.02/
transliterates text between writing systems
----
Lyrics-Fetcher-0.5.0
http://search.cpan.org/~bigpresh/Lyrics-Fetcher-0.5.0/
Perl extension to manage fetchers of song lyrics.
----
M3-ServerView-0.04
http://search.cpan.org/~marwil/M3-ServerView-0.04/
Perl extension for communicating with M3 ServerView
----
Mac-Pasteboard-0.000_04
http://search.cpan.org/~wyant/Mac-Pasteboard-0.000_04/
Manipulate Mac OS X clipboards/pasteboards.
----
Mail-SpamCannibal-0.90
http://search.cpan.org/~miker/Mail-SpamCannibal-0.90/
A tool to stop SPAM
----
Net-SIP-0.42
http://search.cpan.org/~sullr/Net-SIP-0.42/
Framework SIP (Voice Over IP, RFC3261)
----
POE-Component-IRC-5.66
http://search.cpan.org/~bingos/POE-Component-IRC-5.66/
a fully event-driven IRC client module.
----
POE-Component-WWW-PAUSE-RecentUploads-0.04
http://search.cpan.org/~zoffix/POE-Component-WWW-PAUSE-RecentUploads-0.04/
a non-blocking POE wrapper around WWW::PAUSE::RecentUploads.
----
POE-Component-WWW-PAUSE-RecentUploads-0.05
http://search.cpan.org/~zoffix/POE-Component-WWW-PAUSE-RecentUploads-0.05/
a non-blocking POE wrapper around WWW::PAUSE::RecentUploads.
----
POE-Component-WWW-WebDevout-BrowserSupportInfo-0.01
http://search.cpan.org/~zoffix/POE-Component-WWW-WebDevout-BrowserSupportInfo-0.01/
non-blocking access to browser support API on <http://webdevout.net>
----
POEIKC-0.00_03
http://search.cpan.org/~suzuki/POEIKC-0.00_03/
POE IKC daemon and client
----
Sys-Statistics-Linux-0.28
http://search.cpan.org/~bloonix/Sys-Statistics-Linux-0.28/
Front-end module to collect system statistics
----
Text-Markdown-1.0.12
http://search.cpan.org/~bobtfish/Text-Markdown-1.0.12/
Convert MultiMarkdown syntax to (X)HTML
----
Text-Pretty-0.1.0
http://search.cpan.org/~sizur/Text-Pretty-0.1.0/
The great new Text::Pretty!
----
Text-XHTML-0.1
http://search.cpan.org/~sizur/Text-XHTML-0.1/
The great new Text::XHTML!
----
Text-XML-0.1
http://search.cpan.org/~sizur/Text-XML-0.1/
The great new Text::XML!
----
Thread-Queue-2.04
http://search.cpan.org/~jdhedden/Thread-Queue-2.04/
Thread-safe queues
----
Thread-Semaphore-2.05
http://search.cpan.org/~jdhedden/Thread-Semaphore-2.05/
Thread-safe semaphores
----
Types-0.1
http://search.cpan.org/~sizur/Types-0.1/
The great new Types!
----
WWW-WebDevout-BrowserSupportInfo-0.01
http://search.cpan.org/~zoffix/WWW-WebDevout-BrowserSupportInfo-0.01/
----
WebService-Yelp-0.02
http://search.cpan.org/~jdr/WebService-Yelp-0.02/
Yelp.com API Client Implementation
----
XML-RPC-0.7
http://search.cpan.org/~daan/XML-RPC-0.7/
Pure Perl implementation for an XML-RPC client and server.
----
XML-Rules-1.00
http://search.cpan.org/~jenda/XML-Rules-1.00/
parse XML & process tags by rules starting from leaves
----
re-engine-TRE-0.03
http://search.cpan.org/~avar/re-engine-TRE-0.03/
TRE regular expression engine
If you're an author of one of these modules, please submit a detailed
announcement to comp.lang.perl.announce, and we'll pass it along.
This message was generated by a Perl program described in my Linux
Magazine column, which can be found on-line (along with more than
200 other freely available past column articles) at
http://www.stonehenge.com/merlyn/LinuxMag/col82.html
print "Just another Perl hacker," # the original
--
Randal L. Schwartz - Stonehenge Consulting Services, Inc. - +1 503 777 0095
<merlyn@stonehenge.com> <URL:http://www.stonehenge.com/merlyn/>
Perl/Unix/security consulting, Technical writing, Comedy, etc. etc.
See PerlTraining.Stonehenge.com for onsite and open-enrollment Perl training!
------------------------------
Date: Tue, 19 Feb 2008 05:47:16 -0800
From: merlyn@stonehenge.com (Randal L. Schwartz)
Subject: Re: Number of days since 1/1/2000
Message-Id: <86y79hrrbv.fsf@blue.stonehenge.com>
>>>>> "oprah" == oprah chopra <oprah.chopra@gmail.com> writes:
oprah> One problem with Date::Manip is it is not a standard module and not
oprah> available on some of the servers I run the code on. Since my code is
oprah> alrady 100+kb long, I would think requireinf another few hundred kb
oprah> would be overkill for something I can do in one subroutine?
If you are not using Perl in an environment where you can install additional
modules from the CPAN, you are missing out on at least half of what Perl has
to offer.
If an ISP says "we support Perl" and then doesn't give you a way to install
modules in this day and age, I will accuse them of being unethical as a
business.
print "Just another Perl hacker,"; # the original
--
Randal L. Schwartz - Stonehenge Consulting Services, Inc. - +1 503 777 0095
<merlyn@stonehenge.com> <URL:http://www.stonehenge.com/merlyn/>
Perl/Unix/security consulting, Technical writing, Comedy, etc. etc.
See PerlTraining.Stonehenge.com for onsite and open-enrollment Perl training!
------------------------------
Date: Tue, 19 Feb 2008 08:16:18 GMT
From: tadmc@seesig.invalid
Subject: Posting Guidelines for comp.lang.perl.misc ($Revision: 1.8 $)
Message-Id: <mfwuj.2118$Mw.1376@nlpi068.nbdc.sbc.com>
Outline
Before posting to comp.lang.perl.misc
Must
- Check the Perl Frequently Asked Questions (FAQ)
- Check the other standard Perl docs (*.pod)
Really Really Should
- Lurk for a while before posting
- Search a Usenet archive
If You Like
- Check Other Resources
Posting to comp.lang.perl.misc
Is there a better place to ask your question?
- Question should be about Perl, not about the application area
How to participate (post) in the clpmisc community
- Carefully choose the contents of your Subject header
- Use an effective followup style
- Speak Perl rather than English, when possible
- Ask perl to help you
- Do not re-type Perl code
- Provide enough information
- Do not provide too much information
- Do not post binaries, HTML, or MIME
Social faux pas to avoid
- Asking a Frequently Asked Question
- Asking a question easily answered by a cursory doc search
- Asking for emailed answers
- Beware of saying "doesn't work"
- Sending a "stealth" Cc copy
Be extra cautious when you get upset
- Count to ten before composing a followup when you are upset
- Count to ten after composing and before posting when you are upset
-----------------------------------------------------------------
Posting Guidelines for comp.lang.perl.misc ($Revision: 1.8 $)
This newsgroup, commonly called clpmisc, is a technical newsgroup
intended to be used for discussion of Perl related issues (except job
postings), whether it be comments or questions.
As you would expect, clpmisc discussions are usually very technical in
nature and there are conventions for conduct in technical newsgroups
going somewhat beyond those in non-technical newsgroups.
The article at:
http://www.catb.org/~esr/faqs/smart-questions.html
describes how to get answers from technical people in general.
This article describes things that you should, and should not, do to
increase your chances of getting an answer to your Perl question. It is
available in POD, HTML and plain text formats at:
http://www.rehabitation.com/clpmisc.shtml
For more information about netiquette in general, see the "Netiquette
Guidelines" at:
http://andrew2.andrew.cmu.edu/rfc/rfc1855.html
A note to newsgroup "regulars":
Do not use these guidelines as a "license to flame" or other
meanness. It is possible that a poster is unaware of things
discussed here. Give them the benefit of the doubt, and just
help them learn how to post, rather than assume that they do
know and are being the "bad kind" of Lazy.
A note about technical terms used here:
In this document, we use words like "must" and "should" as
they're used in technical conversation (such as you will
encounter in this newsgroup). When we say that you *must* do
something, we mean that if you don't do that something, then
it's unlikely that you will benefit much from this group.
We're not bossing you around; we're making the point without
lots of words.
Do *NOT* send email to the maintainer of these guidelines. It will be
discarded unread. The guidelines belong to the newsgroup so all
discussion should appear in the newsgroup. I am just the secretary that
writes down the consensus of the group.
Before posting to comp.lang.perl.misc
Must
This section describes things that you *must* do before posting to
clpmisc, in order to maximize your chances of getting meaningful replies
to your inquiry and to avoid getting flamed for being lazy and trying to
have others do your work.
The perl distribution includes documentation that is copied to your hard
drive when you install perl. Also installed is a program for looking
things up in that (and other) documentation named 'perldoc'.
You should either find out where the docs got installed on your system,
or use perldoc to find them for you. Type "perldoc perldoc" to learn how
to use perldoc itself. Type "perldoc perl" to start reading Perl's
standard documentation.
Check the Perl Frequently Asked Questions (FAQ)
Checking the FAQ before posting is required in Big 8 newsgroups in
general, there is nothing clpmisc-specific about this requirement.
You are expected to do this in nearly all newsgroups.
You can use the "-q" switch with perldoc to do a word search of the
questions in the Perl FAQs.
Check the other standard Perl docs (*.pod)
The perl distribution comes with much more documentation than is
available for most other newsgroups, so in clpmisc you should also
see if you can find an answer in the other (non-FAQ) standard docs
before posting.
It is *not* required, or even expected, that you actually *read* all of
Perl's standard docs, only that you spend a few minutes searching them
before posting.
Try doing a word-search in the standard docs for some words/phrases
taken from your problem statement or from your very carefully worded
"Subject:" header.
Really Really Should
This section describes things that you *really should* do before posting
to clpmisc.
Lurk for a while before posting
This is very important and expected in all newsgroups. Lurking means
to monitor a newsgroup for a period to become familiar with local
customs. Each newsgroup has specific customs and rituals. Knowing
these before you participate will help avoid embarrassing social
situations. Consider yourself to be a foreigner at first!
Search a Usenet archive
There are tens of thousands of Perl programmers. It is very likely
that your question has already been asked (and answered). See if you
can find where it has already been answered.
One such searchable archive is:
http://groups.google.com/advanced_group_search
If You Like
This section describes things that you *can* do before posting to
clpmisc.
Check Other Resources
You may want to check in books or on web sites to see if you can
find the answer to your question.
But you need to consider the source of such information: there are a
lot of very poor Perl books and web sites, and several good ones
too, of course.
Posting to comp.lang.perl.misc
There can be 200 messages in clpmisc in a single day. Nobody is going to
read every article. They must decide somehow which articles they are
going to read, and which they will skip.
Your post is in competition with 199 other posts. You need to "win"
before a person who can help you will even read your question.
These sections describe how you can help keep your article from being
one of the "skipped" ones.
Is there a better place to ask your question?
Question should be about Perl, not about the application area
It can be difficult to separate out where your problem really is,
but you should make a conscious effort to post to the most
applicable newsgroup. That is, after all, where you are the most
likely to find the people who know how to answer your question.
Being able to "partition" a problem is an essential skill for
effectively troubleshooting programming problems. If you don't get
that right, you end up looking for answers in the wrong places.
It should be understood that you may not know that the root of your
problem is not Perl-related (the two most frequent ones are CGI and
Operating System related), so off-topic postings will happen from
time to time. Be gracious when someone helps you find a better place
to ask your question by pointing you to a more applicable newsgroup.
How to participate (post) in the clpmisc community
Carefully choose the contents of your Subject header
You have 40 precious characters of Subject to win out and be one of
the posts that gets read. Don't waste them. Take care while
composing them, they are the key that opens the door to getting an
answer.
Spend them indicating what aspect of Perl others will find if they
should decide to read your article.
Do not spend them indicating "experience level" (guru, newbie...).
Do not spend them pleading (please read, urgent, help!...).
Do not spend them on non-Subjects (Perl question, one-word
Subject...)
For more information on choosing a Subject see "Choosing Good
Subject Lines":
http://www.cpan.org/authors/id/D/DM/DMR/subjects.post
Part of the beauty of newsgroup dynamics, is that you can contribute
to the community with your very first post! If your choice of
Subject leads a fellow Perler to find the thread you are starting,
then even asking a question helps us all.
Use an effective followup style
When composing a followup, quote only enough text to establish the
context for the comments that you will add. Always indicate who
wrote the quoted material. Never quote an entire article. Never
quote a .signature (unless that is what you are commenting on).
Intersperse your comments *following* each section of quoted text to
which they relate. Unappreciated followup styles are referred to as
"top-posting", "Jeopardy" (because the answer comes before the
question), or "TOFU" (Text Over, Fullquote Under).
Reversing the chronology of the dialog makes it much harder to
understand (some folks won't even read it if written in that style).
For more information on quoting style, see:
http://web.presby.edu/~nnqadmin/nnq/nquote.html
Speak Perl rather than English, when possible
Perl is much more precise than natural language. Saying it in Perl
instead will avoid misunderstanding your question or problem.
Do not say: I have variable with "foo\tbar" in it.
Instead say: I have $var = "foo\tbar", or I have $var = 'foo\tbar',
or I have $var = <DATA> (and show the data line).
Ask perl to help you
You can ask perl itself to help you find common programming mistakes
by doing two things: enable warnings (perldoc warnings) and enable
"strict"ures (perldoc strict).
You should not bother the hundreds/thousands of readers of the
newsgroup without first seeing if a machine can help you find your
problem. It is demeaning to be asked to do the work of a machine. It
will annoy the readers of your article.
You can look up any of the messages that perl might issue to find
out what the message means and how to resolve the potential mistake
(perldoc perldiag). If you would like perl to look them up for you,
you can put "use diagnostics;" near the top of your program.
Do not re-type Perl code
Use copy/paste or your editor's "import" function rather than
attempting to type in your code. If you make a typo you will get
followups about your typos instead of about the question you are
trying to get answered.
Provide enough information
If you do the things in this item, you will have an Extremely Good
chance of getting people to try and help you with your problem!
These features are a really big bonus toward your question winning
out over all of the other posts that you are competing with.
First make a short (less than 20-30 lines) and *complete* program
that illustrates the problem you are having. People should be able
to run your program by copy/pasting the code from your article. (You
will find that doing this step very often reveals your problem
directly. Leading to an answer much more quickly and reliably than
posting to Usenet.)
Describe *precisely* the input to your program. Also provide example
input data for your program. If you need to show file input, use the
__DATA__ token (perldata.pod) to provide the file contents inside of
your Perl program.
Show the output (including the verbatim text of any messages) of
your program.
Describe how you want the output to be different from what you are
getting.
If you have no idea at all of how to code up your situation, be sure
to at least describe the 2 things that you *do* know: input and
desired output.
Do not provide too much information
Do not just post your entire program for debugging. Most especially
do not post someone *else's* entire program.
Do not post binaries, HTML, or MIME
clpmisc is a text only newsgroup. If you have images or binaries
that explain your question, put them in a publically accessible
place (like a Web server) and provide a pointer to that location. If
you include code, cut and paste it directly in the message body.
Don't attach anything to the message. Don't post vcards or HTML.
Many people (and even some Usenet servers) will automatically filter
out such messages. Many people will not be able to easily read your
post. Plain text is something everyone can read.
Social faux pas to avoid
The first two below are symptoms of lots of FAQ asking here in clpmisc.
It happens so often that folks will assume that it is happening yet
again. If you have looked but not found, or found but didn't understand
the docs, say so in your article.
Asking a Frequently Asked Question
It should be understood that you may have missed the applicable FAQ
when you checked, which is not a big deal. But if the Frequently
Asked Question is worded similar to your question, folks will assume
that you did not look at all. Don't become indignant at pointers to
the FAQ, particularly if it solves your problem.
Asking a question easily answered by a cursory doc search
If folks think you have not even tried the obvious step of reading
the docs applicable to your problem, they are likely to become
annoyed.
If you are flamed for not checking when you *did* check, then just
shrug it off (and take the answer that you got).
Asking for emailed answers
Emailed answers benefit one person. Posted answers benefit the
entire community. If folks can take the time to answer your
question, then you can take the time to go get the answer in the
same place where you asked the question.
It is OK to ask for a *copy* of the answer to be emailed, but many
will ignore such requests anyway. If you munge your address, you
should never expect (or ask) to get email in response to a Usenet
post.
Ask the question here, get the answer here (maybe).
Beware of saying "doesn't work"
This is a "red flag" phrase. If you find yourself writing that,
pause and see if you can't describe what is not working without
saying "doesn't work". That is, describe how it is not what you
want.
Sending a "stealth" Cc copy
A "stealth Cc" is when you both email and post a reply without
indicating *in the body* that you are doing so.
Be extra cautious when you get upset
Count to ten before composing a followup when you are upset
This is recommended in all Usenet newsgroups. Here in clpmisc, most
flaming sub-threads are not about any feature of Perl at all! They
are most often for what was seen as a breach of netiquette. If you
have lurked for a bit, then you will know what is expected and won't
make such posts in the first place.
But if you get upset, wait a while before writing your followup. I
recommend waiting at least 30 minutes.
Count to ten after composing and before posting when you are upset
After you have written your followup, wait *another* 30 minutes
before committing yourself by posting it. You cannot take it back
once it has been said.
AUTHOR
Tad McClellan and many others on the comp.lang.perl.misc newsgroup.
--
Tad McClellan
email: perl -le "print scalar reverse qq/moc.noitatibaher\100cmdat/"
------------------------------
Date: 19 Feb 2008 00:00:59 -0500
From: Charlton Wilbur <cwilbur@chromatico.net>
Subject: Re: Regular Expression to Replace UPPER Case Text with lower case text
Message-Id: <87bq6d4k1g.fsf@mithril.chromatico.net>
>>>>> "T" == Tad J McClellan <tadmc@seesig.invalid> writes:
T> ccc31807 <cartercc@gmail.com> wrote:
>> On Feb 18, 9:34 am, RK_78 <riad.ka...@gmail.com> wrote:
>>> Better ideas folks ?
>> Ditch CF and use Perl.
T> What, and get laughed at?
Still much cheaper, and easier on the liver, than the high blood
pressure medication and antidepressants that go along with long-term
ColdFusion exposure.
Charlton
--
Charlton Wilbur
cwilbur@chromatico.net
------------------------------
Date: Tue, 19 Feb 2008 05:42:59 -0800 (PST)
From: ccc31807 <cartercc@gmail.com>
Subject: Re: Regular Expression to Replace UPPER Case Text with lower case text
Message-Id: <76b65c50-a544-4cb2-9cc7-1946fee92a3f@d5g2000hsc.googlegroups.com>
On Feb 18, 5:31 pm, Tad J McClellan
> > Ditch CF and use Perl.
>
> What, and get laughed at?
In the past eight years, I have been constructing web apps using a
variety of technologies, either by choice or because of stated
requirements, including Perl, CF, .NET, JSP, and Python. Recently,
under the influence of writings by Paul Graham and Slava Akhmechet, I
have developed a high degreee of interest in using Lisp. See the links
below.
Using Perl for web apps is controversial to say the least, and I can
sympathize with your little joke. You DO get laughed at if you use
Perl, and that's not a joke. However, Perl has some advantages over
these other technologies, as well as some disadvantages.
I understand that this is OT, but I'm just wondering ... Is there any
good reason I shouldn't learn how to develop web apps in Lisp? I'm
just now taking my first baby steps in constructing Lisp scripts that
spit out HTML with data drawn from data stores, and as far as I can
tell, Lisp potentially has some strengths that Perl does not have (or
CF, .NET, JSP, Python, or any of the others.)
CC
Links:
http://paulgraham.com/avg.html
http://lib.store.yahoo.net/lib/paulgraham/bbnexcerpts.txt
http://www.defmacro.org/ramblings/fp.html
http://www.defmacro.org/ramblings/continuations-web.html
------------------------------
Date: Tue, 19 Feb 2008 12:58:45 +0100
From: Achim Peters <achimpeters@gmx.de>
Subject: Re: Why `for local $var (LIST) ...' not allowed?
Message-Id: <47BAC475.5060705@gmx.de>
Tad J McClellan schrieb:
> Todd <xueweizhong@gmail.com> wrote:
>> Uri Guttman wrote:
>>> do you also know not
>>> to use $a (even in examples)
>> It's only an example.
>
> Don't use $a for anything other than sorting, even in examples.
Agreed, but shouldn't the FAQ be a shining example of that rule? ;-)
* http://faq.perl.org/perlfaq6.html :
| How do I substitute case insensitively on the LHS while
| preserving case on the RHS?
...
| $a = "this is a TEsT case";
| $a =~ s/(test)/preserve_case($1, "success")/egi;
| print "$a\n";
* http://faq.perl.org/perlfaq7.html :
| How do I temporarily block warnings?
...
| $a = $b + $c; # I know these might be undef
and
| Why do Perl operators have different precedence than C operators?
...
| ($maybe ? $a : $b) = $x;
* http://faq.perl.org/perlfaq8.html :
| How do I tell the difference between errors from the shell and perl?
...
| $a = 1 + undef;
Bye
Achim
------------------------------
Date: 6 Apr 2001 21:33:47 GMT (Last modified)
From: Perl-Users-Request@ruby.oce.orst.edu (Perl-Users-Digest Admin)
Subject: Digest Administrivia (Last modified: 6 Apr 01)
Message-Id: <null>
Administrivia:
#The Perl-Users Digest is a retransmission of the USENET newsgroup
#comp.lang.perl.misc. For subscription or unsubscription requests, send
#the single line:
#
# subscribe perl-users
#or:
# unsubscribe perl-users
#
#to almanac@ruby.oce.orst.edu.
NOTE: due to the current flood of worm email banging on ruby, the smtp
server on ruby has been shut off until further notice.
To submit articles to comp.lang.perl.announce, send your article to
clpa@perl.com.
#To request back copies (available for a week or so), send your request
#to almanac@ruby.oce.orst.edu with the command "send perl-users x.y",
#where x is the volume number and y is the issue number.
#For other requests pertaining to the digest, send mail to
#perl-users-request@ruby.oce.orst.edu. Do not waste your time or mine
#sending perl questions to the -request address, I don't have time to
#answer them even if I did know the answer.
------------------------------
End of Perl-Users Digest V11 Issue 1289
***************************************
