[25526] in Perl-Users-Digest
Perl-Users Digest, Issue: 7770 Volume: 10
daemon@ATHENA.MIT.EDU (Perl-Users Digest)
Fri Feb 11 06:05:47 2005
Date: Fri, 11 Feb 2005 03:05:15 -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 Fri, 11 Feb 2005 Volume: 10 Number: 7770
Today's topics:
Re: [perl-python] combinatorics fun <xah@xahlee.org>
Re: [perl-python] combinatorics fun <onurb@xiludom.gro>
Re: decompiling perl2exe files <ian@itcontracts.biz>
Re: FAQ 7.3 Do I always/never have to quote my strings <abigail@abigail.nl>
Image::Magick trouble <alexj@floor.ch>
Re: Is there a more idiomatic way to do this? <junk@blackwater-pacific.com>
Re: Is there a more idiomatic way to do this? <someone@example.com>
Re: Lexical scoping question. <zen13097@zen.co.uk>
module installation trouble <alexj@floor.ch>
Re: module installation trouble <alexj@floor.ch>
Re: Perl on freebsd: max memory limit? <do-not-use@invalid.net>
Re: perl telnet (not www) bbs? <andrew.wyatt@fewt.com>
Re: perl telnet (not www) bbs? <noonespecial@myplace.org>
Posting Guidelines for comp.lang.perl.misc ($Revision: tadmc@augustmail.com
Re: rename captures in regex <toddrw69@excite.com>
Digest Administrivia (Last modified: 6 Apr 01) (Perl-Users-Digest Admin)
----------------------------------------------------------------------
Date: 10 Feb 2005 22:38:20 -0800
From: "Xah Lee" <xah@xahlee.org>
Subject: Re: [perl-python] combinatorics fun
Message-Id: <1108103900.874115.41120@z14g2000cwz.googlegroups.com>
David Eppstein's code is very nice.
Here's the python version of the perl code:
=A9# -*- coding: utf-8 -*-
=A9# Python
=A9
=A9def combo (n):
=A9 '''returns all possible (unordered) pairs out of n numbers 1 to
n=2E
=A9
=A9 Returns a dictionary. The keys are of the form "n,m",
=A9 and their values are tuples. e.g. combo(4) returns
=A9 {'3,4': (3, 4), '1,4': (1, 4), '1,2': (1, 2),
=A9 '1,3': (1, 3), '2,4': (2, 4), '2,3': (2, 3)}'''
=A9 result=3D{}
=A9 for j in range(1,n):
=A9 for i in range(1,n+1):
=A9 m =3D ((i+j)-1) % n + 1
=A9 if (i < m):
=A9 result["%d,%d"%(i,m)]=3D(i,m)
=A9 return result
=A9
=A9print combo(4)
So sweet.
Xah
xah@xahlee.org
http://xahlee.org/PageTwo_dir/more.html
------------------------------
Date: Fri, 11 Feb 2005 11:05:28 +0100
From: bruno modulix <onurb@xiludom.gro>
Subject: Re: [perl-python] combinatorics fun
Message-Id: <420c836e$0$19204$626a14ce@news.free.fr>
YYUsenet wrote:
> Xah Lee wrote:
>
(snip insanities)
>>
>
> Why are you posting this to comp.lang.python? This obviously has nothing
> to do with python at all. If you are trying to teach people python,
> claiming that "...let's do a python version. I'll post my version later
> today." Isn't really the proper way to do it. An even better method
> would be to set up a website dedicated to nothing but it, and stop
> posting here with garbage code that no one wants to read, and that helps
> no one. Please, consider others a little bit when you go off on your
> wild hope that you might be able to teach other people what you
> obviously know nothing about, teaching people from a language that you
> know nothing about. *PLEASE STOP POSTING*!! *NOBODY WANTS YOU TO POST*!!
>
The guy is an obvious, well-known and self-proclaimed troll. Dont feed
the troll.
--
bruno desthuilliers
ruby -e "print 'onurb@xiludom.gro'.split('@').collect{|p|
p.split('.').collect{|w| w.reverse}.join('.')}.join('@')"
--
------------------------------
Date: 11 Feb 2005 01:58:07 -0800
From: "ian@itcontracts.biz" <ian@itcontracts.biz>
Subject: Re: decompiling perl2exe files
Message-Id: <1108115887.342226.144270@z14g2000cwz.googlegroups.com>
Lambik wrote:
> IanT wrote:
>
> > hi and help
> > someone at this organisation has wiped out the source code for the
> > perl scripts which we had converted to .exe files with Indigostar's
> > perl2exe utility.
> > Does anyone in this forum have any ideas how we can recover the
> > scripts in their original form; the person who wrote the scripts
has
> > shuffled off this mortal coil, so we can't use that route for
> > recovery.
> >
> > tia - Ian
>
> In a dutch NG they gave http://www.net-security.org/vuln.php?id=2464
> this link to the same question.
Thanks, but I'd been there; what I need is the info at the link that is
mentioned there to the Simon Cozens website which now appears to be
broken.
Ta - Ian
------------------------------
Date: 11 Feb 2005 07:59:23 GMT
From: Abigail <abigail@abigail.nl>
Subject: Re: FAQ 7.3 Do I always/never have to quote my strings or use semicolons and commas?
Message-Id: <slrnd0oper.g2.abigail@alexandra.abigail.nl>
Martin Gregory (martin.gregory@freescale.com) wrote on MMMMCLXXXII
September MCMXCIII in <URL:news:cuh9o5$173$1@az33news01.freescale.net>:
??
?? Why do we use "" when '' will do?
??
?? Isn't "" more work for perl (since it has to look to see if it
?? needs to interpolate)?
Why are you programming in Perl if such a difference matters to you?
Abigail
--
perl -le 's[$,][join$,,(split$,,($!=85))[(q[0006143730380126152532042307].
q[41342211132019313505])=~m[..]g]]e and y[yIbp][HJkP] and print'
------------------------------
Date: Fri, 11 Feb 2005 11:21:17 +0100
From: Alexandre Jaquet <alexj@floor.ch>
Subject: Image::Magick trouble
Message-Id: <cui0ur$a48$1@news.hispeed.ch>
Hi I just install ImageMagick for windows and I got a strange problem
I can execute demo.pl but when I try to edit it and execute with Komodo
I got compilation error.
Image::Magick is not recognized.
Thx in advance
------------------------------
Date: Thu, 10 Feb 2005 22:01:46 -0800
From: Steve May <junk@blackwater-pacific.com>
Subject: Re: Is there a more idiomatic way to do this?
Message-Id: <110oi0fiui5an0c@corp.supernews.com>
Alan Mead wrote:
> I recently created a script that did a lot of this sort of thing:
>
> my $dataref = get_data($filename1) if ($condition==1);
> my $dataref = get_data($filename2) if ($condition==2);
>
> foreach my $datum (keys %$dataref) { ...
>
> Which didn't raise an exception but $dataref was always nil. I had to
> write:
>
> my $dataref;
> $dataref = get_data($filename1) if ($condition==1);
> $dataref = get_data($filename2) if ($condition==2);
>
> I'm not sure I understand precisely why the first one didn't work but
> also failed to raise an error when run under the strict pragma. I
> mean, if it was a scoping thing then shouldn't the reference to
> %$dataref in the foreach loop trigger an exception?
>
> Anyway, the second method fixed the problem but it's a bit ungainly. Is
> there a more idiomatic way to do this?
>
> Thanks,
>
> -Alan
>
I suppose a hash might be more perlish:
my %files = (
1 => 'filename1',
2 => 'filename2',
};
my $dataref = '';
$files{$condition} and $dataref = get_data( $files{$condition} );
$dataref or do_something_else;
or something along those lines....
I'm sure you'll get more suggestions.
\s
------------------------------
Date: Fri, 11 Feb 2005 09:17:46 GMT
From: "John W. Krahn" <someone@example.com>
Subject: Re: Is there a more idiomatic way to do this?
Message-Id: <_K_Od.48200$tU6.23607@edtnps91>
Alan Mead wrote:
> I recently created a script that did a lot of this sort of thing:
>
> my $dataref = get_data($filename1) if ($condition==1);
> my $dataref = get_data($filename2) if ($condition==2);
>
> foreach my $datum (keys %$dataref) { ...
>
> Which didn't raise an exception but $dataref was always nil. I had to
> write:
>
> my $dataref;
> $dataref = get_data($filename1) if ($condition==1);
> $dataref = get_data($filename2) if ($condition==2);
>
> I'm not sure I understand precisely why the first one didn't work
It is explained in perlsyn.pod in the 'Statement Modifiers' section:
perldoc perlsyn
[snip]
NOTE: The behaviour of a "my" statement modified with a statement
modifier conditional or loop construct (e.g. "my $x if ...") is
undefined. The value of the "my" variable may be "undef", any
previously assigned value, or possibly anything else. Don't rely on
it. Future versions of perl might do something different from the
version of perl you try it out on. Here be dragons.
> but
> also failed to raise an error when run under the strict pragma. I
> mean, if it was a scoping thing then shouldn't the reference to
> %$dataref in the foreach loop trigger an exception?
No. As long as the argument to keys() is a hash it will not complain.
$ perl -le'use warnings;use strict; my $x; for ( keys %$x ) { print }'
$ perl -le'use warnings;use strict; my $x; for ( keys $x ) { print }'
Type of arg 1 to keys must be hash (not private variable) at -e line 1, near
"$x ) "
Execution of -e aborted due to compilation errors.
$ perl -le'use warnings;use strict; my $x; for ( keys @$x ) { print }'
Type of arg 1 to keys must be hash (not array dereference) at -e line 1, near
"$x ) "
Execution of -e aborted due to compilation errors.
> Anyway, the second method fixed the problem but it's a bit ungainly. Is
> there a more idiomatic way to do this?
Yes. Use an array for the filenames.
die "Range error for \$condition\n"
if $condition < 1 or $condition > @filenames;
my $dataref = get_data( $filenames[ $condition - 1 ] );
John
--
use Perl;
program
fulfillment
------------------------------
Date: 11 Feb 2005 08:45:00 GMT
From: Dave Weaver <zen13097@zen.co.uk>
Subject: Re: Lexical scoping question.
Message-Id: <420c708c$0$32620$db0fefd9@news.zen.co.uk>
On Thu, 10 Feb 2005 14:56:35 +0100, Louis <louis@despammed.com> wrote:
> The below script will print "var is apple". I find this weird, because
> in textbooks you are taught to pass variable to subroutines as
> parameters. What is the point of doing this, if the variable is
> visible anyway?
> my $var = "apple";
> routine();
>
> sub routine {
> print "var is $var.\n";
> }
One of the problems with doing things this way (i.e. using 'global'
variables) is that routine() above can only process $var. If routine()
is non-trivial (as most subs are) and you wanted to do the same
process on a different variable, you'd have a problem. Good
programming is all about re-use - you can't re-use routine() in the
code above; it has one (very limited) use.
A sub-routine should be a 'black box' - it should (generally) take
some input (via parameters, not global variables), do some processing,
and return some output (via the 'return' statement, not global
variables). You then have a software 'brick' that you can test
individually, and can use in more than one situation.
> {
> my $var = "apple";
> routine($var);
> }
>
> sub routine {
> my $var = $_[0];
> print "var is $var.\n";
> }
But here you can use routine() to process *any* variable, making it
vastly more flexible. There is the added advantage (as long as
routine() doesn't directly modify @_) that changes to $var aren't
hidden away in a subroutine (action at a distance, which makes
maintenance a complete pain).
Put another way, which do you think is clearer, this:
my $var = "apple";
routine();
$var = "orange";
routine()
sub routine {
print "var is $var.\n";
}
or this:
routine( 'apple' );
routine( 'orange' );
sub routine {
my $var = shift;
print "var is $var\n";
}
I, like many self-taught programmers I know, initially wrote
programs with a myriad of global variables and little/no parameter
passing, just as in your first example. I soon learnt that down
this road lies madness - bugs are more prevelant and harder to find,
and nobody (including myself) could understand how it all worked a
couple of yeats later.
Fortunately, my coding skills have improved enormously since then! :-)
------------------------------
Date: Fri, 11 Feb 2005 10:02:52 +0100
From: Alexandre Jaquet <alexj@floor.ch>
Subject: module installation trouble
Message-Id: <cuhsbr$uan$1@news.hispeed.ch>
Hi, I got some error after trying to install module trough ppm.
I type the following command ppm install DBI
and then run a simple script to test the drivers currently installed
here is the message errors:
install_driver(Proxy) failed: Can't locate RPC/PlClient.pm in @INC (@INC
contains: . C:\Program Files\ActiveState Komodo 3.0\dbgp\perllib
C:/Perl/lib C:/Perl/site/lib .) at C:/Perl/site/lib/DBD/Proxy.pm line 28.
BEGIN failed--compilation aborted at C:/Perl/site/lib/DBD/Proxy.pm line 28.
Compilation failed in require at (eval 13)[C:/Perl/site/lib/DBI.pm:707]
line 3.
Perhaps a module that DBD::Proxy requires hasn't been fully installed
I've try to do ppm install PlClient but didn't find anything.
Any idea ?
thanks in advance
------------------------------
Date: Fri, 11 Feb 2005 10:27:42 +0100
From: Alexandre Jaquet <alexj@floor.ch>
Subject: Re: module installation trouble
Message-Id: <cuhtqd$2ac$1@news.hispeed.ch>
Alexandre Jaquet a écrit :
> Hi, I got some error after trying to install module trough ppm.
>
> I type the following command ppm install DBI
>
> and then run a simple script to test the drivers currently installed
> here is the message errors:
>
>
> install_driver(Proxy) failed: Can't locate RPC/PlClient.pm in @INC (@INC
> contains: . C:\Program Files\ActiveState Komodo 3.0\dbgp\perllib
> C:/Perl/lib C:/Perl/site/lib .) at C:/Perl/site/lib/DBD/Proxy.pm line 28.
> BEGIN failed--compilation aborted at C:/Perl/site/lib/DBD/Proxy.pm line 28.
> Compilation failed in require at (eval 13)[C:/Perl/site/lib/DBI.pm:707]
> line 3.
> Perhaps a module that DBD::Proxy requires hasn't been fully installed
>
> I've try to do ppm install PlClient but didn't find anything.
>
> Any idea ?
>
> thanks in advance
Hi find a way to correct that using :
http://www.mail-archive.com/dbi-users@perl.org/msg14130.html
------------------------------
Date: 11 Feb 2005 10:07:47 +0100
From: Arndt Jonasson <do-not-use@invalid.net>
Subject: Re: Perl on freebsd: max memory limit?
Message-Id: <yzdbrar31ng.fsf@invalid.net>
Abigail <abigail@abigail.nl> writes:
> John Bokma (postmaster@castleamber.com) wrote on MMMMCLXXXI September
> MCMXCIII in <URL:news:Xns95F945C91EFCcastleamber@130.133.1.4>:
> <> Is there a max memory limit for a Perl process on freebsd? A script bombs
> <> out when it uses close to 512 MB. (I have no direct access to the machine,
> <> just asking for someone).
>
>
> Perl itself doesn't have memory limits. However, memory is limited to
> what the OS is willing to give to the process. How much memory Perl
> can get at most determines on the amount of memory available in total,
> the memory used by other processes, and any process limits.
If a 'perl' running on a 32-bit machine can address only 2^32 bytes of
memory, isn't that a memory limit?
(I don't know the architecture of 'perl' - maybe there are type bits
and stuff that make the effective range less.)
(The language Perl probably doesn't stipulate any minimum or maximum
amount of usable memory. Or does it?)
------------------------------
Date: Fri, 11 Feb 2005 05:09:22 GMT
From: Andrew Wyatt <andrew.wyatt@fewt.com>
Subject: Re: perl telnet (not www) bbs?
Message-Id: <66XOd.8667$oO.2369@newsread2.news.atl.earthlink.net>
gargoyle wrote:
> Do they exist? Google isn't very helpful. I found something called
> Fusion GS, but the links are all broken.
>
> Just wondering... I'd rather write my own, but at the same time I'd
> like to see what's been done before.
WOW, I didn't realize that Fusion was still googlable. :-) I sold my rights
to Fusion v3 a few years back, so I really can't give away that code to
even the 2.x version. Send an email to awyatt _at_ gmail _dot_ com and I'll
pass the request on to it's current owner. I've since written another BBS,
and I was really happy with it. It included a teleconference etc, but I no
longer have time to maintain it. I can send a copy of that code if you are
interested.
-Andrew
------------------------------
Date: Fri, 11 Feb 2005 05:14:26 GMT
From: Andrew Wyatt <noonespecial@myplace.org>
Subject: Re: perl telnet (not www) bbs?
Message-Id: <SaXOd.8702$oO.4150@newsread2.news.atl.earthlink.net>
Andrew Wyatt wrote:
> gargoyle wrote:
>
>> Do they exist? Google isn't very helpful. I found something called
>> Fusion GS, but the links are all broken.
>>
>> Just wondering... I'd rather write my own, but at the same time I'd
>> like to see what's been done before.
>
> WOW, I didn't realize that Fusion was still googlable. :-) I sold my
> rights to Fusion v3 a few years back, so I really can't give away that
> code to even the 2.x version. Send an email to awyatt _at_ gmail _dot_ com
> and I'll pass the request on to it's current owner. I've since written
> another BBS, and I was really happy with it. It included a teleconference
> etc, but I no longer have time to maintain it. I can send a copy of that
> code if you are interested.
>
> -Andrew
http://sourceforge.net/projects/fusiongs/
That's the last free version that's still out on the web (that *I* know of).
------------------------------
Date: 11 Feb 2005 08:22:14 GMT
From: tadmc@augustmail.com
Subject: Posting Guidelines for comp.lang.perl.misc ($Revision: 1.5 $)
Message-Id: <420c6b35$0$23560$8b463f8a@news.nationwide.net>
Outline
Before posting to comp.lang.perl.misc
Must
- Check the Perl Frequently Asked Questions (FAQ)
- Check the other standard Perl docs (*.pod)
Really Really Should
- Lurk for a while before posting
- Search a Usenet archive
If You Like
- Check Other Resources
Posting to comp.lang.perl.misc
Is there a better place to ask your question?
- Question should be about Perl, not about the application area
How to participate (post) in the clpmisc community
- Carefully choose the contents of your Subject header
- Use an effective followup style
- Speak Perl rather than English, when possible
- Ask perl to help you
- Do not re-type Perl code
- Provide enough information
- Do not provide too much information
- Do not post binaries, HTML, or MIME
Social faux pas to avoid
- Asking a Frequently Asked Question
- Asking a question easily answered by a cursory doc search
- Asking for emailed answers
- Beware of saying "doesn't work"
- Sending a "stealth" Cc copy
Be extra cautious when you get upset
- Count to ten before composing a followup when you are upset
- Count to ten after composing and before posting when you are upset
-----------------------------------------------------------------
Posting Guidelines for comp.lang.perl.misc ($Revision: 1.5 $)
This newsgroup, commonly called clpmisc, is a technical newsgroup
intended to be used for discussion of Perl related issues (except job
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As you would expect, clpmisc discussions are usually very technical in
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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:
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Must
This section describes things that you *must* do before posting to
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have others do your work.
The perl distribution includes documentation that is copied to your hard
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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
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Checking the FAQ before posting is required in Big 8 newsgroups in
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The perl distribution comes with much more documentation than is
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Try doing a word-search in the standard docs for some words/phrases
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Really Really Should
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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
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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
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too, of course.
Posting to comp.lang.perl.misc
There can be 200 messages in clpmisc in a single day. Nobody is going to
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Your post is in competition with 199 other posts. You need to "win"
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These sections describe how you can help keep your article from being
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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,
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You have 40 precious characters of Subject to win out and be one of
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For more information on choosing a Subject see "Choosing Good
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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 <tadmc@augustmail.com> and many others on the
comp.lang.perl.misc newsgroup.
------------------------------
Date: Fri, 11 Feb 2005 05:07:10 GMT
From: "Todd W" <toddrw69@excite.com>
Subject: Re: rename captures in regex
Message-Id: <24XOd.3617$ng6.792@newssvr17.news.prodigy.com>
<ioneabu@yahoo.com> wrote in message
news:1108095518.553809.61610@o13g2000cwo.googlegroups.com...
>
> Todd W wrote:
> > A factory function we have makes some stupid assumptions about the
> data it
> > is parsing. I give it content and a regex, and it gives me back an
> array.
> >
> > Is there any way, for example, to tell capture 1 of a regex to store
> its
> > value in $2?
> >
> > Here is the output of the program below.
> >
> > [trwww@waveright misc]$ perl cap.pl
> > One:
> > title: bar
> > link: foo
> > descr: bazz
> > Two:
> > title: bazz
> > link: bar
> > descr: foo
> >
> > Is there any way to make the output of "One:" identical to the output
> of
> > "Two:" by changing ONLY the the string stored in $reg2?
>
>
> >
> > use warnings;
> > use strict;
> >
> > my $str1 = '<a href="foo">bar</a><div>bazz</div>';
> > my $reg1 = '<a href="([^"]+)">([^<]+)</a><div>([^<]+)<';
> >
> > $str1 =~ m|$reg1|;
> >
> > print("One:
> > title: $2
> > link: $1
> > descr: $3
> > ");
> >
> > my $str2 = '<div>bar</div><div>bazz</div><a href="foo">readmore</a>';
> >
> > ### modify only this regex
> > my $reg2 = '<div>([^<]+)</div><div>([^<]+)</div><a href="([^"]+)"';
> >
> >
> > $str2 =~ m|$reg2|;
> >
>
> Sorry if I'm not getting the problem, but it seems that this would do
> it:
>
> my ($title, $link, $descr) = ($1, $3, $2);
>
> print("Two:
> title: $title
> link: $link
> descr: $descr
> ");
>
>
> wana
>
The only solutions that will work for me are ones that involve changing ONLY
the $reg2 variable. Any other changes would require modification of a
function that I can not modify.
Someone else has posted a solution in another branch.
Thanks for replying, though =0)
Todd W.
------------------------------
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)
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End of Perl-Users Digest V10 Issue 7770
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