[24373] in Perl-Users-Digest
Perl-Users Digest, Issue: 6562 Volume: 10
daemon@ATHENA.MIT.EDU (Perl-Users Digest)
Fri May 14 09:05:51 2004
Date: Fri, 14 May 2004 06:05:10 -0700 (PDT)
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, 14 May 2004 Volume: 10 Number: 6562
Today's topics:
Re: "my" variables and recursive regexp strangeness (Ian)
Re: Datetime overflow with DBI ODBC setting 19th centur <irhm@clara.net>
Re: Datetime overflow with DBI ODBC setting 19th centur <nobull@mail.com>
delete emptyline / new line in a file in perl program <velu_jayashree@yahoo.com>
Re: delete emptyline / new line in a file in perl progr <josef.moellers@fujitsu-siemens.com>
Re: delete emptyline / new line in a file in perl progr <tadmc@augustmail.com>
file uploads (Sokar)
Re: file uploads <noreply@gunnar.cc>
get values from the textbox in perl TK <velu_jayashree@yahoo.com>
Re: Module/recipe to resolve full pathnames? <nobull@mail.com>
Net::SCP::Expect problem (Magnus)
Re: Net::SCP::Expect problem <vetro@online.no>
Re: Perldoc versus Man <tadmc@augustmail.com>
Re: Perldoc versus Man <tadmc@augustmail.com>
Posting Guidelines for comp.lang.perl.misc ($Revision: tadmc@augustmail.com
Re: Random Integer <tadmc@augustmail.com>
Re: Regular Expression Help? - Newbie Question <tore@aursand.no>
Re: Rounding a Number <tadmc@augustmail.com>
Re: Stopping code execution in RE's <nobull@mail.com>
Re: Why Carp::croak over die? (Anno Siegel)
Digest Administrivia (Last modified: 6 Apr 01) (Perl-Users-Digest Admin)
----------------------------------------------------------------------
Date: 14 May 2004 05:59:08 -0700
From: ijnetnews@hotmail.com (Ian)
Subject: Re: "my" variables and recursive regexp strangeness
Message-Id: <942d3706.0405140459.1772e986@posting.google.com>
Jeff 'japhy' Pinyan <pinyaj@rpi.edu> wrote in message news:<Pine.SGI.3.96.1040513173428.1309961A-100000@vcmr-64.server.rpi.edu>...
> [posted & mailed]
>
> Someone has already answered this. You can't declare and use the
> lexical variable on the same line.
First thanks to you and the other 2 posters for answering the
question. I hadn't known that "my" variables need to be declared that
way. I would have thought that it ought to be a candidate for a
warning message when I used it that way though. Anyhoo...
> I've stripped out everything but the double-quoted regexes. WHY are these
> recursive? I don't see the value of that at all.
Well, why they were recursive was because I couldn't get it to work in
a non-recursive way :-) so I decided to do it in a yacc like way, and
got it to work, albeit in a non-scalable way.
As you showed, there was no need for the recursion. I had felt that
there must have been a simpler way, and that was one of my questions.
Why not just
>
> $dStringData = qr{ (?: [^"\\] | \\. )+ }xs;
> $string = qr{ " $dStringData " }x;
>
> $dStringData is not gaining anything by being recursive, since once the
> non-closing-quote stuff matches, the next thing that will match *is* the
> closing quote. So it "recurses" once. Unless, of course, you never match
> a closing quote, in which case your regex tries a whole bunch of
> permutations before failing.
>
> Run this code:
>
> print "slow\n";
> $rx = qr{ (?: [^\\"] | \\. )+ (??{ $rx }) | " }x;
> q{"this thing is too slow} =~ m{ " (??{ $rx }) }x;
> print "done\n\n";
>
> print "fast\n";
> $rx = qr{ (?: [^\\"] | \\. )+ }x;
> q{"this thing is too slow} =~ m{ " $rx " }x;
> print "done\n\n";
>
> You'll see the bottom one is MUCH MUCH faster. The reason the top one is
> slow is because after it fails the first time, the (?:...)+ part
> backtracks a bit, and then the (??{ $rx }) can match the part it didn't
> match, and then it tries to match a " and fails, and it does this more and
> more and more. Every character you add to that string results in a
> quadratically longer wait. I took out the "!" at the end of the string
> because I got impatient!
Ah, this explains the warning that perl was giving me when I ran with
perl -W. It was saying something like that it was matching the null
string many times. Sure enough, when I remove the + like you suggest
in your other post the warning goes away.
Jeff 'japhy' Pinyan <pinyaj@rpi.edu> wrote in message news:<Pine.SGI.3.96.1040513174539.1323146A-100000@vcmr-64.server.rpi.edu>...
> On Thu, 13 May 2004, Jeff 'japhy' Pinyan wrote:
>
> >Run this code:
> >
> > print "slow\n";
> > $rx = qr{ (?: [^\\"] | \\. )+ (??{ $rx }) | " }x;
> > q{"this thing is too slow} =~ m{ " (??{ $rx }) }x;
> > print "done\n\n";
>
> This becomes MUCH MUCH faster if you change $rx to
>
> $rx = qr{ (?: [^\\"] | \\. ) (??{ $rx }) | " }x;
>
> Note that there is no + quantifier on the (?:...) group.
Yes, this is faster. I tested, and this increases execution time at
the same rate as the non-recursive one, though your non-recursive one
is 2 times faster always.
------------------------------
Date: Fri, 14 May 2004 08:29:41 +0100
From: "iain" <irhm@clara.net>
Subject: Re: Datetime overflow with DBI ODBC setting 19th century dates with placeholders
Message-Id: <40a47549$0$22311$4c56ba96@master.news.zetnet.net>
"James Willmore" <jwillmore@remove.adelphia.net> wrote in message
news:pan.2004.05.14.04.44.19.763862@remove.adelphia.net...
> > $sth->execute('1900-01-01'); # works OK
> > $sth->execute('1799-12-31'); # gives error
>
> First ... try to insert the date using the command line utility for the
> RDBMS. If it works, then it *should* work in the script. If it doesn't,
> then the issue lies with the RDBMS.
>
> Next, you could use the 'debug' function in the DBI module to see what the
> "conversation" is between the script and the database. That will shed
> some light on why it's not working as expected.
>
> There are more ideas, but give these a try first :-)
>
> HTH
>
> --
> Jim
>
Thanks for the suggestion, but I've tried both those - $dbh->trace(5) shows
the date is passed to SQL Server ODBC driver in the same way for both 1901
and 1799.
BTW - I meant to show 1899 not 1799 in my original post - neither work
anyway.
The command line utility (SQL Query) only allows you to use complete SQL DML
statements, not placeholders with parameters (as far as I know). And the
former works fine for 1899 with perl DBI anyway.
It seems to be something to do with ODBC not binding the date parameter
correctly when it would be held as a negative number on the database.
I've also tried the SQL Server profiler on the server side, but haven't got
it to show sufficient detail for
this kind of update.
Iain
------------------------------
Date: 14 May 2004 13:13:50 +0100
From: Brian McCauley <nobull@mail.com>
Subject: Re: Datetime overflow with DBI ODBC setting 19th century dates with placeholders
Message-Id: <u9pt97ury9.fsf@wcl-l.bham.ac.uk>
"iain" <irhm@clara.net> writes:
> I'm trying to update 19th century dates in SQL Server.
>
> It works fine with dates on or after 1 Jan 1900, but not before. It is also
> OK if the 19th century dates are included as literals in the SQL INSERT or
> UPDATE command (with $dbh->do or prepare/execute)
>
> Error message: DBD::ODBC::st execute failed: [Microsoft][ODBC SQL Server
> Driver]Datetime field overflow (SQL-22008)(DBD: st_execute/SQLExecute
> err=-1) at Pat_DOB_error_report.pl line 13.
I've hit this problem too.
> I've tried all kinds of options like bind_param, SQL_DATE, CAST(? as
> datetime). It seems to be interpreted as a date, but the actual year is not
> being processed correctly.
>
> I'm not sure if this is a SQL Server or DBD::ODBC issue. I am using recent
> versions of everything.
I'm not sure either. It could also be in ODBC itself or in the ODBC
driver for MSSQL.
It seems that somewhere along the line all datetime placeholders are
treated as short. One day I'm going to have to investigate.
> Any ideas for correction or workaround?
Other than not using placeholders, no.
--
\\ ( )
. _\\__[oo
.__/ \\ /\@
. l___\\
# ll l\\
###LL LL\\
------------------------------
Date: Fri, 14 May 2004 04:42:06 -0400
From: "maami" <velu_jayashree@yahoo.com>
Subject: delete emptyline / new line in a file in perl program
Message-Id: <80d124eb2c28ccd6c1ffca7e4bb55eed@localhost.talkaboutprogramming.com>
Hai
one question.
i want to delete the unwanted or say empty file / newline in the file.
eg:
iam happy
iam very happy
iam cheerful
..
..
so on.
but i want to remove the space between the Iam very happy and iam
cheerful
plz let me know it fastly.
regards,
Jayashree
------------------------------
Date: Fri, 14 May 2004 13:46:15 +0200
From: =?ISO-8859-1?Q?Josef_M=F6llers?= <josef.moellers@fujitsu-siemens.com>
Subject: Re: delete emptyline / new line in a file in perl program
Message-Id: <c82bb4$fnm$1@nntp.fujitsu-siemens.com>
maami wrote:
> Hai
> one question.
> i want to delete the unwanted or say empty file / newline in the file.=
>=20
> eg:
> iam happy
> iam very happy
>=20
> iam cheerful
> ..
> ..
> so on.
> but i want to remove the space between the Iam very happy and iam
> cheerful
>=20
>=20
> plz let me know it fastly.
Here's the usual question: What have you tried so far and where did it=20
not work.
This is a veeery trivial question.
--=20
Josef M=F6llers (Pinguinpfleger bei FSC)
If failure had no penalty success would not be a prize
-- T. Pratchett
------------------------------
Date: Fri, 14 May 2004 07:29:44 -0500
From: Tad McClellan <tadmc@augustmail.com>
Subject: Re: delete emptyline / new line in a file in perl program
Message-Id: <slrnca9eto.b18.tadmc@magna.augustmail.com>
maami <velu_jayashree@yahoo.com> wrote:
> one question.
Which is Asked Frequently.
> i want to delete the unwanted or say empty file / newline in the file.
^^^^^^
perldoc -q delete
How do I change one line in a file/delete a line in a file/insert a
line in the middle of a file/append to the beginning of a file?
You are expected to check the Perl FAQ *before* posting to
the Perl newsgroup.
> plz let me know it fastly.
Yes sir. Right away sir.
--
Tad McClellan SGML consulting
tadmc@augustmail.com Perl programming
Fort Worth, Texas
------------------------------
Date: 14 May 2004 04:28:40 -0700
From: jmccloughlin@hotmail.com (Sokar)
Subject: file uploads
Message-Id: <34628238.0405140328.7163a7f4@posting.google.com>
I have a perl cgi form that when activated prints out an online for
for people to fil in. I want to give the user the option to upload
two jpegs. I have the input type "file" I just dont know how to
upload the picture onto my server. The cgi calls a .pl script. When
I do a $pic1 = $FORM{'pic1'} all i get is the path name that the user
submitted when they selected the pic they want to upload.
I was told that I would prob have to use cgi.pm to get this done.
Would anyone have a bit of code that will upload the jpeg file that
the user selects and save it onto my server?
Thanks in advance
------------------------------
Date: Fri, 14 May 2004 13:40:02 +0200
From: Gunnar Hjalmarsson <noreply@gunnar.cc>
Subject: Re: file uploads
Message-Id: <2gjpgdF3juf8U1@uni-berlin.de>
Sokar wrote:
> I want to give the user the option to upload two jpegs.
<snip>
> I was told that I would prob have to use cgi.pm to get this done.
Sounds to be a decent advice.
> Would anyone have a bit of code that will upload the jpeg file that
> the user selects and save it onto my server?
I take for granted that you checked out the documentation for CGI.pm,
and tried to apply the code snippets that are provided there. Can you
please let us know which part of the docs you did not understand?
You are welcome to post a short but complete program here with your
best shot as to uploading a file. If you do, I believe that somebody
will help you fix possible errors.
--
Gunnar Hjalmarsson
Email: http://www.gunnar.cc/cgi-bin/contact.pl
------------------------------
Date: Fri, 14 May 2004 04:53:45 -0400
From: "maami" <velu_jayashree@yahoo.com>
Subject: get values from the textbox in perl TK
Message-Id: <4f4ee4efdf43ef4b0f0cf89ada21416f@localhost.talkaboutprogramming.com>
Hai
I want to get the values from the text box when u typed it in the
run time.
how to get the values and how to put the same in the another same text.
regards,
Jayashree
------------------------------
Date: 14 May 2004 13:31:49 +0100
From: Brian McCauley <nobull@mail.com>
Subject: Re: Module/recipe to resolve full pathnames?
Message-Id: <u9hdujur4a.fsf@wcl-l.bham.ac.uk>
kj <socyl@987jk.com> writes:
> Is there a module (or built-in) that will take an arbitary Unix
> filename specification (either absolute or relative) and return
> the "canonical" absolute full path to the file?
Yes there's more than one. For example there's Cwd::abs_path.
Note: 95% of the time when people think they want to do this they are
wrong. If the user specifies a path in a particular form you need to
have a damn good reason to change it. Most of the time people's
reason for wanting to do this come down to "I thought it looked
tidier". This is not a good reason.
> input: ~jones/../foo/../../bar/./baz//frobozz/
> output: /bar/baz/frobozz
Ah, you've moved the goalposts. That's not an arbitary Unix filename
specification (either absolute or relative) - that's something else.
See FAQ: "How can I translate tildes (~) in a filename?"
--
\\ ( )
. _\\__[oo
.__/ \\ /\@
. l___\\
# ll l\\
###LL LL\\
------------------------------
Date: 14 May 2004 02:45:37 -0700
From: mapal@home.se (Magnus)
Subject: Net::SCP::Expect problem
Message-Id: <f2463108.0405140145.5002f92c@posting.google.com>
Hi,
I´m having problems with Net::SCP::Expect.
My script looks like this:
my $scpe = Net::SCP::Expect->new(user=>'$username',password=>'$password',
preserve=>1, recursive=>1, verbose=>1);
$scpe->scp('$host:/home/foo/','/destination');
If I run this script as root the scripts try to connect as root, not
as the user I´ve set in $username. If I run the script as the same
user as $username
it will be correct but it ask for password. The password is correct,
when I run a manual scp and enter the same password it works...
I´m running slackware 9.1 on both servers and using OpenSSH_3.7.1p2
and OpenSSH_3.8p1.
What can be wrong?
Thanks.
Regards,
Magnus
------------------------------
Date: Fri, 14 May 2004 11:56:22 +0200
From: "Vetle Roeim" <vetro@online.no>
Subject: Re: Net::SCP::Expect problem
Message-Id: <opr7zhv8xi3hk3cf@quickfix.opera.com>
On 14 May 2004 02:45:37 -0700, Magnus <mapal@home.se> wrote:
> Hi,
> I´m having problems with Net::SCP::Expect.
>
> My script looks like this:
>
> my $scpe =
> Net::SCP::Expect->new(user=>'$username',password=>'$password',
> preserve=>1, recursive=>1, verbose=>1);
> $scpe->scp('$host:/home/foo/','/destination');
Is this your code? If so, then you should be using double quotes (")
instead of single quotes (').
Try this instead:
my $scpe = Net::SCP::Expect->new(user => $username,
password => $password,
preserve => 1,
recursive => 1,
verbose=>1);
$scpe->scp("$host:/home/foo/",'/destination');
With the double quote ("), the values of the variables are inserted
into the string. This does not happen with the single quote (').
[...]
--
Touch eyeballs to screen for cheap laser surgery!
------------------------------
Date: Thu, 13 May 2004 23:51:34 -0500
From: Tad McClellan <tadmc@augustmail.com>
Subject: Re: Perldoc versus Man
Message-Id: <slrnca8k2m.a0k.tadmc@magna.augustmail.com>
Edward Wijaya <ewijaya@singnet.com.sg> wrote:
> I have only "man perl" at my Linux toolbox.
Why don't you have perldoc installed?
It is part of a normal install of perl itself.
Do you have some kind of custom installation?
Maybe it _is_ installed but you just don't know where...
--
Tad McClellan SGML consulting
tadmc@augustmail.com Perl programming
Fort Worth, Texas
------------------------------
Date: Thu, 13 May 2004 23:55:21 -0500
From: Tad McClellan <tadmc@augustmail.com>
Subject: Re: Perldoc versus Man
Message-Id: <slrnca8k9p.a0k.tadmc@magna.augustmail.com>
Uri Guttman <uri@stemsystems.com> wrote:
>>>>>> "EW" == Edward Wijaya <ewijaya@singnet.com.sg> writes:
>
> EW> Is there any content and usability difference between
> EW> perldoc and man.
> for basic printing of a perl doc page they are equivilent.
> but perldoc does know about various parts of the docs that man doesn't
> and that is what those extra options do.
And perldoc knows even more than all that.
It knows how to display the docs for core modules.
It knows how to display the docs for modules installed from CPAN.
It knows how to display the docs for your own modules (provided you
are clever enough to write documentation for your modules :-)
--
Tad McClellan SGML consulting
tadmc@augustmail.com Perl programming
Fort Worth, Texas
------------------------------
Date: Fri, 14 May 2004 02:23:00 -0500
From: tadmc@augustmail.com
Subject: Posting Guidelines for comp.lang.perl.misc ($Revision: 1.5 $)
Message-Id: <nvKdnWy-rYRJ7jndRVn-gg@august.net>
Outline
Before posting to comp.lang.perl.misc
Must
- Check the Perl Frequently Asked Questions (FAQ)
- Check the other standard Perl docs (*.pod)
Really Really Should
- Lurk for a while before posting
- Search a Usenet archive
If You Like
- Check Other Resources
Posting to comp.lang.perl.misc
Is there a better place to ask your question?
- Question should be about Perl, not about the application area
How to participate (post) in the clpmisc community
- Carefully choose the contents of your Subject header
- Use an effective followup style
- Speak Perl rather than English, when possible
- Ask perl to help you
- Do not re-type Perl code
- Provide enough information
- Do not provide too much information
- Do not post binaries, HTML, or MIME
Social faux pas to avoid
- Asking a Frequently Asked Question
- Asking a question easily answered by a cursory doc search
- Asking for emailed answers
- Beware of saying "doesn't work"
- Sending a "stealth" Cc copy
Be extra cautious when you get upset
- Count to ten before composing a followup when you are upset
- Count to ten after composing and before posting when you are upset
-----------------------------------------------------------------
Posting Guidelines for comp.lang.perl.misc ($Revision: 1.5 $)
This newsgroup, commonly called clpmisc, is a technical newsgroup
intended to be used for discussion of Perl related issues (except job
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://mail.augustmail.com/~tadmc/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
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 <tadmc@augustmail.com> and many others on the
comp.lang.perl.misc newsgroup.
------------------------------
Date: Thu, 13 May 2004 23:59:08 -0500
From: Tad McClellan <tadmc@augustmail.com>
Subject: Re: Random Integer
Message-Id: <slrnca8kgs.a0k.tadmc@magna.augustmail.com>
Mike Lepore <lepor5e@bestweb.net> wrote:
> Does someone have a subroutine I can use to generate a
> random integer between 0 and integer n, inclusive?
perldoc -q random
How do I get a random number between X and Y?
I hope you are suitably embarrassed.
--
Tad McClellan SGML consulting
tadmc@augustmail.com Perl programming
Fort Worth, Texas
------------------------------
Date: Fri, 14 May 2004 12:04:21 +0200
From: Tore Aursand <tore@aursand.no>
Subject: Re: Regular Expression Help? - Newbie Question
Message-Id: <pan.2004.05.11.17.10.51.469273@aursand.no>
On Tue, 11 May 2004 16:13:04 +0000, Vik Rubenfeld wrote:
> <MTRegexDefine name="RemoveBoldFacing1">s|^\s*<b>||gi</MTRegexDefine>
> <MTRegexDefine name="RemoveBoldFacing2">s|\s*<\b>||gi</MTRegexDefine>
Don't know what this is, but you could try replacing '<\b>' with the
correct HTML tag, which is '</b>'. Depending on the the system using the
regular expressions, you might also need to escape the slash; '<\/b>'.
And why use '^\s*' and '\s*' above? I don't think you'll ever need them.
Be sure to also strip '<strong>' and '</strong>' while you're at it. They
are (legal) HTML tags.
--
Tore Aursand <tore@aursand.no>
"Out of missiles. Out of bullets. Down to harsh language." (Unknown)
------------------------------
Date: Thu, 13 May 2004 23:59:51 -0500
From: Tad McClellan <tadmc@augustmail.com>
Subject: Re: Rounding a Number
Message-Id: <slrnca8ki7.a0k.tadmc@magna.augustmail.com>
Uri Guttman <uri@stemsystems.com> wrote:
>>>>>> "ML" == Mike Lepore <lepor5e@bestweb.net> writes:
>
> ML> How can I round a number to the nearest n decimal places?
> FAQ
I hope he is suitably embarrassed.
--
Tad McClellan SGML consulting
tadmc@augustmail.com Perl programming
Fort Worth, Texas
------------------------------
Date: 14 May 2004 13:21:21 +0100
From: Brian McCauley <nobull@mail.com>
Subject: Re: Stopping code execution in RE's
Message-Id: <u9lljvurlq.fsf@wcl-l.bham.ac.uk>
Matthew Braid <mb@uq.net.au.invalid> writes:
> I'm writing a formatter package that basically has a little language
> of its own to allow joombie users format their own stuff without
> bothering me....
>
> One of the formatter 'tags' allows the use of a regular expression (in
> a slightly stunted fashion), however I want to ensure no code
> execution is performed.
Then do _not_ put...
use re 'eval';
...in your programs.
If you are really paranoid put...
no re 'eval';
...just before you compile the regex (either explicitly with qr// or
implicitly by using a variable containing something other than a
compiled regex in a regex context).
But like I said, no eval is the default anyhow.
--
\\ ( )
. _\\__[oo
.__/ \\ /\@
. l___\\
# ll l\\
###LL LL\\
------------------------------
Date: 14 May 2004 12:16:53 GMT
From: anno4000@lublin.zrz.tu-berlin.de (Anno Siegel)
Subject: Re: Why Carp::croak over die?
Message-Id: <c82dbl$ja4$1@mamenchi.zrz.TU-Berlin.DE>
Ben Morrow <usenet@morrow.me.uk> wrote in comp.lang.perl.misc:
[...]
> When I'm writing modules, I use carp/croak for things which are the
> user's fault, and warn/die for things which are my fault (obviously,
> such things never happen :).
In fact, "can't happen" situations are the only ones where a module
should call "die" instead of "croak".
Corollary: Debugged modules never die, they only croak.
Anno
------------------------------
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:
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------------------------------
End of Perl-Users Digest V10 Issue 6562
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