[30724] in Perl-Users-Digest
Perl-Users Digest, Issue: 1969 Volume: 11
daemon@ATHENA.MIT.EDU (Perl-Users Digest)
Fri Nov 7 09:09:52 2008
Date: Fri, 7 Nov 2008 06:09:16 -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, 7 Nov 2008 Volume: 11 Number: 1969
Today's topics:
Re: A couple of questions regarding runtime generation <bik.mido@tiscalinet.it>
Re: A couple of questions regarding runtime generation sln@netherlands.com
Re: A couple of questions regarding runtime generation sln@netherlands.com
CPAN config for local mirror <abc@def.com>
Re: determine when to change to or from daylight saving <rvtol+news@isolution.nl>
Re: determine when to change to or from daylight saving <placebo@petergreen.id.au>
Re: determine when to change to or from daylight saving <RedGrittyBrick@spamweary.invalid>
Re: determine when to change to or from daylight saving <rvtol+news@isolution.nl>
Re: determine when to change to or from daylight saving sln@netherlands.com
Re: determine when to change to or from daylight saving <r.ted.byers@gmail.com>
Re: determine when to change to or from daylight saving <r.ted.byers@gmail.com>
fastest way to monitor a dir perl.coder@ny.com
Re: Odd regular expression behaviour <jcombe@gmail.com>
Re: Odd regular expression behaviour <jcombe@gmail.com>
Posting Guidelines for comp.lang.perl.misc ($Revision: tadmc@seesig.invalid
python feature in perl? <mikee@mikee.ath.cx>
Should sophisticated Regexp solutions be pay as you go sln@netherlands.com
Re: SUBSTR() with replacement or lvalue performance iss <bik.mido@tiscalinet.it>
Digest Administrivia (Last modified: 6 Apr 01) (Perl-Users-Digest Admin)
----------------------------------------------------------------------
Date: Fri, 07 Nov 2008 10:38:19 +0100
From: Michele Dondi <bik.mido@tiscalinet.it>
Subject: Re: A couple of questions regarding runtime generation of REGEXP's
Message-Id: <nt28h4t80cf4qcl49viotdj8lp68oa3icj@4ax.com>
On Wed, 05 Nov 2008 19:54:14 GMT, sln@netherlands.com wrote:
>I settled on this lightweight class that handles the substution with some
>variable type's. Still it is with minimal error checking to reduce overhead.
>Added a few methods to generalize access, and it benchmarks pretty good.
>
>See any potential problems or performance issues ?
I don't have time enough to dig through your implementation, but it
seems to me that you set up a fairly complete thingie: now,
performance is not generally a concern of mine. If it is for you, then
just profile your app. For the rest, I can only suggest you to set up
a test suite as well. As far as your implementation complies, you may
consider yourself reasonalby safe, ain't it?
Michele
--
{$_=pack'B8'x25,unpack'A8'x32,$a^=sub{pop^pop}->(map substr
(($a||=join'',map--$|x$_,(unpack'w',unpack'u','G^<R<Y]*YB='
.'KYU;*EVH[.FHF2W+#"\Z*5TI/ER<Z`S(G.DZZ9OX0Z')=~/./g)x2,$_,
256),7,249);s/[^\w,]/ /g;$ \=/^J/?$/:"\r";print,redo}#JAPH,
------------------------------
Date: Fri, 07 Nov 2008 10:51:03 GMT
From: sln@netherlands.com
Subject: Re: A couple of questions regarding runtime generation of REGEXP's
Message-Id: <h378h4lpqqd2io7kchl3orqaltfmq0d6dr@4ax.com>
On Fri, 07 Nov 2008 10:38:19 +0100, Michele Dondi <bik.mido@tiscalinet.it> wrote:
>On Wed, 05 Nov 2008 19:54:14 GMT, sln@netherlands.com wrote:
>
>>I settled on this lightweight class that handles the substution with some
>>variable type's. Still it is with minimal error checking to reduce overhead.
>>Added a few methods to generalize access, and it benchmarks pretty good.
>>
>>See any potential problems or performance issues ?
>
>I don't have time enough to dig through your implementation, but it
>seems to me that you set up a fairly complete thingie: now,
>performance is not generally a concern of mine. If it is for you, then
>just profile your app. For the rest, I can only suggest you to set up
>a test suite as well. As far as your implementation complies, you may
>consider yourself reasonalby safe, ain't it?
>
>
>Michele
Never heard of test suites/cases. On my really big app, I'm making changes
so fast it scares me. I miss a compiler as opposed to a syntax checker.
No, no. Nunit isin't for me. I live on the edge, die on the edge, one
man - one piece of art...
sln
------------------------------
Date: Fri, 07 Nov 2008 11:22:51 GMT
From: sln@netherlands.com
Subject: Re: A couple of questions regarding runtime generation of REGEXP's
Message-Id: <ej88h41k4a6rm1jh8u33hcbcs0q6bqcsd8@4ax.com>
On Fri, 07 Nov 2008 10:38:19 +0100, Michele Dondi <bik.mido@tiscalinet.it> wrote:
>On Wed, 05 Nov 2008 19:54:14 GMT, sln@netherlands.com wrote:
>
>>I settled on this lightweight class that handles the substution with some
>>variable type's. Still it is with minimal error checking to reduce overhead.
>>Added a few methods to generalize access, and it benchmarks pretty good.
>>
>>See any potential problems or performance issues ?
>
>I don't have time enough to dig through your implementation, but it
>seems to me that you set up a fairly complete thingie: now,
>performance is not generally a concern of mine. If it is for you, then
>just profile your app. For the rest, I can only suggest you to set up
>a test suite as well. As far as your implementation complies, you may
>consider yourself reasonalby safe, ain't it?
>
>
>Michele
I've already integrated this package into my bigger package and have exported
a thin wrapper sub that instantiates objects which are used as a drop in
by the caller, specifically used as a parameter (a ref from NewRxP) that
gets passed to the larger package method. Like a macro almost.
I'm learning the gory details of classes in Perl, something I didn't think
I would need to know beyond casual knowledge. I'm a hard core Windows
MFC C++ programmer, its how I make my living as a contractor.
Periodically, I'm laid off, like now. Perl is like candy to me, sweet to the
tongue, especially regular expressions. Its almost addicting. Unemployment is
running out, nobody is calling, I'm sure I will have to give this up and work
as a brick layer, my long past proffession, again. So, if I dissapear, its
been nice knowing you!
sln
------------------------------
Date: Fri, 07 Nov 2008 12:54:59 +0000
From: zaphod <abc@def.com>
Subject: CPAN config for local mirror
Message-Id: <4vednflBXr0-p4nUnZ2dnUVZ8vKdnZ2d@posted.plusnet>
I run a local CPAN mirror for offline development purposes and update it
every 2 to 4 weeks on average. Every time I run:
# cpan -i <module>
I get this (modified):
Could not find '/<user>/cpan/mirror/authors/01mailrc.txt.gz'
Fetching with LWP:
file://Users/<user>/cpan/mirror/authors/01mailrc.txt.gz
CPAN: YAML loaded ok (v0.66)
Going to read /var/root/.cpan/sources/authors/01mailrc.txt.gz
CPAN: Compress::Zlib loaded ok (v2.012)
............................................................................DONE
Could not find '/<user>/cpan/mirror/modules/02packages.details.txt.gz'
Fetching with LWP:
file://Users/<user>/cpan/mirror/modules/02packages.details.txt.gz
Going to read /var/root/.cpan/sources/modules/02packages.details.txt.gz
Database was generated on Mon, 15 Sep 2008 01:02:49 GMT
Warning: This index file is 53 days old.
Please check the host you chose as your CPAN mirror for staleness.
I'll continue but problems seem likely to happen.
............................................................................DONE
Could not find '/<user>/cpan/mirror/modules/03modlist.data.gz'
Fetching with LWP:
file://Users/<user>/cpan/mirror/modules/03modlist.data.gz
Going to read /var/root/.cpan/sources/modules/03modlist.data.gz
............................................................................DONE
I would like to have CPAN.pm bypass this check so that I can install modules
more quickly. Any suggestions for changing the CPAN.pm config?
Zaphod
------------------------------
Date: Fri, 7 Nov 2008 09:05:31 +0100
From: "Dr.Ruud" <rvtol+news@isolution.nl>
Subject: Re: determine when to change to or from daylight savings time
Message-Id: <gf10hd.29k.1@news.isolution.nl>
Ted Byers schreef:
> Ilya Zakharevich:
>> $ENV{TZ} = 'US/Pacific';
>> POSIX::settz(); # sp? tzset()?
>> print scalar localtime time;
>>
>> and get the correct local time.
>
> What you suggest is applicable to various tasks on my own machine, but
> actually I already have that working already. My problem involves
> converting times that apply to one institution on the other side of
> the planet into timezones that are on the other side of this
> continent. I don't see how working wih my own local time helps.
Huh? Just put a different timezone string in $ENV{TZ}, right?
--
Affijn, Ruud
"Gewoon is een tijger."
------------------------------
Date: Fri, 07 Nov 2008 09:42:05 GMT
From: "Peter Wyzl" <placebo@petergreen.id.au>
Subject: Re: determine when to change to or from daylight savings time
Message-Id: <N3UQk.11775$sc2.8565@news-server.bigpond.net.au>
"Dr.Ruud" <rvtol+news@isolution.nl> wrote in message
news:gf10hd.29k.1@news.isolution.nl...
> Ted Byers schreef:
>> Ilya Zakharevich:
>
>>> $ENV{TZ} = 'US/Pacific';
>>> POSIX::settz(); # sp? tzset()?
>>> print scalar localtime time;
>>>
>>> and get the correct local time.
>>
>> What you suggest is applicable to various tasks on my own machine, but
>> actually I already have that working already. My problem involves
>> converting times that apply to one institution on the other side of
>> the planet into timezones that are on the other side of this
>> continent. I don't see how working wih my own local time helps.
>
> Huh? Just put a different timezone string in $ENV{TZ}, right?
Yes but is there some 'authorative source' of what all the different
timezones are and the daylight times for those zones and when they switch
back and forth?
P
------------------------------
Date: Fri, 07 Nov 2008 10:51:46 +0000
From: RedGrittyBrick <RedGrittyBrick@spamweary.invalid>
Subject: Re: determine when to change to or from daylight savings time
Message-Id: <49141dc3$0$2528$da0feed9@news.zen.co.uk>
Peter Wyzl wrote:
> is there some 'authorative source' of what all the different
> timezones are and the daylight times for those zones and when they
> switch back and forth?
>
Since those things are a matter of political whim I doubt there is a
source I would be happy labelling authoritative for the whole planet.
Try
http://www.twinsun.com/tz/tz-link.htm
--
RGB
------------------------------
Date: Fri, 7 Nov 2008 12:26:00 +0100
From: "Dr.Ruud" <rvtol+news@isolution.nl>
Subject: Re: determine when to change to or from daylight savings time
Message-Id: <gf1c78.1r8.1@news.isolution.nl>
Peter Wyzl schreef:
> but is there some 'authorative source' of what all the different
> timezones are and the daylight times for those zones and when they
> switch back and forth?
I use DateTime::TimeZone which uses Olson. Good enough for me.
http://search.cpan.org/search?query=timezone&mode=module
--
Affijn, Ruud
"Gewoon is een tijger."
------------------------------
Date: Fri, 07 Nov 2008 11:39:59 GMT
From: sln@netherlands.com
Subject: Re: determine when to change to or from daylight savings time
Message-Id: <07a8h4h6ld1f1if78a9jfqt3iaajgkfep8@4ax.com>
On Fri, 07 Nov 2008 10:51:46 +0000, RedGrittyBrick <RedGrittyBrick@spamweary.invalid> wrote:
>
>Peter Wyzl wrote:
>> is there some 'authorative source' of what all the different
>> timezones are and the daylight times for those zones and when they
>> switch back and forth?
>>
>
>Since those things are a matter of political whim I doubt there is a
>source I would be happy labelling authoritative for the whole planet.
>
>Try
>http://www.twinsun.com/tz/tz-link.htm
Its the alias for $GOD
sln
------------------------------
Date: Fri, 7 Nov 2008 05:42:06 -0800 (PST)
From: Ted Byers <r.ted.byers@gmail.com>
Subject: Re: determine when to change to or from daylight savings time
Message-Id: <c208d5c3-33e8-41b7-aaad-62bcacf6a011@v13g2000pro.googlegroups.com>
On Nov 7, 3:05=A0am, "Dr.Ruud" <rvtol+n...@isolution.nl> wrote:
> Ted Byers schreef:
>
> > Ilya Zakharevich:
> >> $ENV{TZ} =3D 'US/Pacific';
> >> POSIX::settz(); # sp? tzset()?
> >> print scalar localtime time;
>
> >> and get the correct local time.
>
> > What you suggest is applicable to various tasks on my own machine, but
> > actually I already have that working already. =A0My problem involves
> > converting times that apply to one institution on the other side of
> > the planet into timezones that are on the other side of this
> > continent. =A0I don't see how working wih my own local time helps.
>
> Huh? Just put a different timezone string in $ENV{TZ}, right?
>
> --
> Affijn, Ruud
>
> "Gewoon is een tijger."
Actually no. This is to interact with a database on a server that
serves a web application. Messing with the environment settings on
the server for the timezone is guaranteed to fail. For example, there
could be simultaneous requests for data applicable to different
locations. Something like the function Date_ConvTZ($date,$from,$to)
in Date::Manip is required instead but which would make use of the
olson database you mentioned in another post to know when either
timezone should use daylight saving time.
Since you said you use DateTime::TimeZone, can you tell me an example
of how to use it to take a date that, say, ParseDate($string), from
Date::Manip, would return and convert it from one timezone to another
using Olson's database to taking daylight saving time into account (in
effect making something like Date_ConvTZ that would work with the
EST5EDT that Date::Manip uses in other functions).
Thanks
Ted
------------------------------
Date: Fri, 7 Nov 2008 05:50:34 -0800 (PST)
From: Ted Byers <r.ted.byers@gmail.com>
Subject: Re: determine when to change to or from daylight savings time
Message-Id: <379083a9-2302-48f1-9af0-49c45b737dcb@40g2000prx.googlegroups.com>
On Nov 7, 6:39=A0am, s...@netherlands.com wrote:
> On Fri, 07 Nov 2008 10:51:46 +0000, RedGrittyBrick <RedGrittyBr...@spamwe=
ary.invalid> wrote:
>
> >Peter Wyzl wrote:
> >> is there some 'authorative source' of what all the different
> >> timezones are and the daylight times for those zones and when they
> >> switch back and forth?
>
> >Since those things are a matter of political whim I doubt there is a
> >source I would be happy labelling authoritative for the whole planet.
>
> >Try
> >http://www.twinsun.com/tz/tz-link.htm
>
> Its the alias for $GOD
>
> sln
That gives you the olson data that Dr Ruud mentioned. I have
downloaded that and am presently trying to figure out how to use it.
found a couple scripts in the timezone project: parse_olson and
update_from_latest_olson. I can't use the latter since it is written
explicitly using programs and paths found on Unix and not, normally,
on Windows, but parse_olson looks like it may work for me. I'll know
later today if it does. But I am still looking through the
documentation for DateTime::TimeZone to see how to use it to convert,
e.g., a time from UTC to "EST5EDT" (as defined in Date::Manip), using
either EST or EDT on the right dates.
Thanks
Ted
------------------------------
Date: 7 Nov 2008 06:06:04 -0800
From: perl.coder@ny.com
Subject: fastest way to monitor a dir
Message-Id: <gf1i0c0113u@drn.newsguy.com>
Hi,
I have a perl script running in production which takes a file name
to be scanned continuously and call a user exit shell program
to take action when a string it is looking for is found in
the file. All I do is to sleep for few seconds and wake
and check the size of the file and if it has changed
since last scanned, scan the new lines added since last
scan.
Now the specs has changed. We recently found that
some server process don't write to the same file,
but create a new file (usually timestamped) when
some error condition happens. So now my script
also has to change accordingly. From just monitoring
a file constantly, it also has to monitor the dir to
see whether a new file has been dropped and then start
monitoring it (also stop the earlier file it was monitoring).
So my question is, what is the fastest way to check whether
a new file has arrived in a directory. The new file name
will always have a fixed prefix, with a changing suffix
every time (usually timestamp).
Thanks in advance.
------------------------------
Date: Fri, 7 Nov 2008 05:47:39 -0800 (PST)
From: Jon Combe <jcombe@gmail.com>
Subject: Re: Odd regular expression behaviour
Message-Id: <0b37d878-e54b-431c-9291-c66b0d36dc63@n33g2000pri.googlegroups.com>
> Yes, /g starts from where the last match left. IIRC, reset pos to 0 to
> avoid that and have a (better) look at perldoc perlre.
OK thanks for the explanation. The problem is the "perlre" document
for the version of Perl I'm using makes no mention of the g modifier
at all. The only mention I can find is in the pos document itself. I
see that online versions of the document do mention this behaviour,
but it is not mentioned in the documentation for any of the versions
of Perl I have available.
------------------------------
Date: Fri, 7 Nov 2008 05:48:10 -0800 (PST)
From: Jon Combe <jcombe@gmail.com>
Subject: Re: Odd regular expression behaviour
Message-Id: <f08c012c-11c5-4c48-984a-a330f7cc852a@d42g2000prb.googlegroups.com>
> Maybe you want to use index:
Yes I think I do - thanks!
Jon
------------------------------
Date: Fri, 07 Nov 2008 08:10:11 GMT
From: tadmc@seesig.invalid
Subject: Posting Guidelines for comp.lang.perl.misc ($Revision: 1.8 $)
Message-Id: <DJSQk.5856$x%.4691@nlpi070.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
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As you would expect, clpmisc discussions are usually very technical in
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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
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For more information about netiquette in general, see the "Netiquette
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A note to newsgroup "regulars":
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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,
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Checking the FAQ before posting is required in Big 8 newsgroups in
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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
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Check the other standard Perl docs (*.pod)
The perl distribution comes with much more documentation than is
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It is *not* required, or even expected, that you actually *read* all of
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Try doing a word-search in the standard docs for some words/phrases
taken from your problem statement or from your very carefully worded
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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
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customs. Each newsgroup has specific customs and rituals. Knowing
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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
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Your post is in competition with 199 other posts. You need to "win"
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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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Carefully choose the contents of your Subject header
You have 40 precious characters of Subject to win out and be one of
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Spend them indicating what aspect of Perl others will find if they
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Do not spend them on non-Subjects (Perl question, one-word
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For more information on choosing a Subject see "Choosing Good
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http://www.cpan.org/authors/id/D/DM/DMR/subjects.post
Part of the beauty of newsgroup dynamics, is that you can contribute
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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: Fri, 7 Nov 2008 03:08:51 +0000 (UTC)
From: Mike <mikee@mikee.ath.cx>
Subject: python feature in perl?
Message-Id: <gf0bg3$1sq$1@registered.motzarella.org>
I like that in python you can say:
if __name__ == "__main__"
tests
To know if you are running a $module.py file stand alone or if the
$module.py file has been included into a different, super python
script. Is there a similar feature in PERL? I've been using PERL
for a long time and I don't remember anything like this. I can think
of a way to emulate the feature, but I prefer to have a built in
instead of an emulation hack.
Mike
------------------------------
Date: Fri, 07 Nov 2008 10:15:25 GMT
From: sln@netherlands.com
Subject: Should sophisticated Regexp solutions be pay as you go requested?
Message-Id: <3t48h4lkqlcng2isb60nho9can3iof1evf@4ax.com>
I've noticed alot of complex regular expression problems posted here that require
alot of thought.
Should there be monetary compensation for such complex solutions?
sln
------------------------------
Date: Fri, 07 Nov 2008 11:41:21 +0100
From: Michele Dondi <bik.mido@tiscalinet.it>
Subject: Re: SUBSTR() with replacement or lvalue performance issues
Message-Id: <bs38h49bu6oanughiuvgdgr8rfen2v8fh0@4ax.com>
On Fri, 07 Nov 2008 02:17:58 GMT, sln@netherlands.com wrote:
>Apart from like, copy from the start of a matched position, to a
>file (as opposed to another buffer), then catenating the modification
>to the file, then continue on with the next match, is the substr
>(lvalue or replacement) a viable option?
>
>I have to consider performance on such large operations.
ISTR that the lvaluedness of substr()'s return value, as long as the
fact that you can EVEN take references of it and modify the string
with a sort of action-at-distance was put there specifically for
performance issues. At some point there were problems with
substitutions having a lenght larger than the substituted IalsoIRC,
but they should be solved in recent enough perls.
See: <http://perlmonks.org/?node_id=498434>
Michele
--
{$_=pack'B8'x25,unpack'A8'x32,$a^=sub{pop^pop}->(map substr
(($a||=join'',map--$|x$_,(unpack'w',unpack'u','G^<R<Y]*YB='
.'KYU;*EVH[.FHF2W+#"\Z*5TI/ER<Z`S(G.DZZ9OX0Z')=~/./g)x2,$_,
256),7,249);s/[^\w,]/ /g;$ \=/^J/?$/:"\r";print,redo}#JAPH,
------------------------------
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>
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------------------------------
End of Perl-Users Digest V11 Issue 1969
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