[29181] in Perl-Users-Digest
Perl-Users Digest, Issue: 425 Volume: 11
daemon@ATHENA.MIT.EDU (Perl-Users Digest)
Fri May 11 06:09:40 2007
Date: Fri, 11 May 2007 03:09:03 -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, 11 May 2007 Volume: 11 Number: 425
Today's topics:
Re: Any way to access global variable in Perl script fr <Michael.Yxf@gmail.com>
Re: DBD::Oracle, tracing, and stored procedures... (Heinrich Mislik)
Re: How to concatenate cookies <nobull67@gmail.com>
How to restart all hashes and arrays halfway through sc <csoon@xilinx.com>
Re: I'd like to create an array of unique values <sujay.tukai@gmail.com>
Identify if a scalar is int, double or text <klaus03@gmail.com>
Posting Guidelines for comp.lang.perl.misc ($Revision: tadmc@augustmail.com
Re: warnings dilemma <nobull67@gmail.com>
Digest Administrivia (Last modified: 6 Apr 01) (Perl-Users-Digest Admin)
----------------------------------------------------------------------
Date: 11 May 2007 01:15:20 -0700
From: Michael Yang <Michael.Yxf@gmail.com>
Subject: Re: Any way to access global variable in Perl script from one module file?
Message-Id: <1178871320.097552.79070@w5g2000hsg.googlegroups.com>
On May 11, 2:43 pm, Brian McCauley <nobul...@gmail.com> wrote:
> On 11 May, 06:03, Michael Yang <Michael....@gmail.com> wrote:
>
> > On May 11, 1:07 am, Brian McCauley <nobul...@gmail.com> wrote:
> > > On May 10, 1:38 pm, Michael Yang <Michael....@gmail.com> wrote:
> > > > How can I call Testrunner.pl from main.pl without spawning a separate
> > > > child process?
> > > You could do() it. However this would possibly give odd effects if you
> > > try to call Testrunner.pl more than once from main.pl.
> > I am thinking about using 'require' to do this:
> > @ARGV = ();
> > require 'Testrunner.pl';
>
> > In this way, the variable defined in the main script is in the same
> > context as the Testrunner.pl, and could be accessed from the module
> > file.
>
> Yes that's what I said. Well I said do() not require(). But the only
> difference in this conext is that main.pl _cannot_ run Testrunner.pl
> more than once.
>
> > But I found it slows the harness greatly, the performance is lowered.
>
> That seems highly counter-intuative. I would expect it to be a little
> faster as you are only loading perl once.
>
> How are you observing this? Is it possible that it's not the tests
> that are running slowly but rather something like an output buffering
> issue?
>
> > How to leaverage on this?
>
> Well the bunderbus thing would be to make a copy of the whole thing,
> main.pl, Testrunner.pl and at least one test case and check you still
> see the difference. Then cut bits out progressively checking at each
> stage that you still see the difference.
>
> Eventually you'll have a minimal but complete test case to illustrate
> the behaviour. If but this time you've not spotted what's happening
> then you should post the three files (which by now should be <20 lines
> each).
Thanks for your pointing it out, Brian.
There is indeed the output buffering codes in the script, but I
thought it works fine.
Since it's a harness containing serveral large scripts, that I can't
paste each piece of the codes, so I only put the key parts of the
codes to simply illustrate what I am doing. Also the codes that might
have relationship with output buffering.
### my main.pl script ####
### <codes omitted>####
## Start calling the Testrunner.pl ###
@ARGV = ( "$testcase", ###The file with list of testcases in xml
format
"$paramFile", ###The file containing the
configuration data
"$logfile"); ###The file that log data is
written to.
do "$<path to runner>/Testrunner.pl";
if ($@){
#### codes to deal with errors ####
}
###<codes omitted>####
### End of main.pl script ###
#### Testrunner.pl script #######
### <codes to process parameters passed by main.pl> omitted###
### Set the autoflush to ON ####
$| = 1;
### <codes to process list of testcases> omitted###
### Start to run the testcase subroutines in each module####
foreach my $sr (@routines)
{
select STDOUT; #route print statements to STDOUT
$logHandler->write($sr) # write the testcase info into logfile,
defined in another module
print "\n\t Executing => $sr";
select $logFileHandle; # route print statements to the logfile,
the one passed into by main.pl
eval
{
no strict "refs";
($sr) -> ($params); #execution of the subroutines contained
in each testcase module
}
}
#### <codes dealing with the rest> omitted ####
#### End of Testrunner.pl #####
### The module for one testcases, case1.pm#####
package case1;
#### <codes dealing with the member variables> omitted ####
sub test1
{
####<codes omitted> ####
###This will be directed to the logfile specified by the "select
$logFileHandle" in Testrunner.pl#####
print "Executing the test1...\n";
$output = `...`; ## There is one child process spawned here, I
saved the output into one variable.
### <rest of codes> omitted ####
}
### <codes left> omitted ####
1;
#####End of case1.pm #######
I just looked throught, and think these parts might have something
with output buffering issue if there is any.
These work fine and fast by invoking Testrunner.pl by spawning a child
process, as discussed previously, except for the problem that the
variable in main.pl can not be accessed from case1.pm.
I am not sure which will affect and cause the buffering issues. If you
have any simple example, could you show me one that might block the I/
O that I could look into it?
Thanks so much!
------------------------------
Date: 11 May 2007 08:22:23 GMT
From: Heinrich.Mislik@univie.ac.at (Heinrich Mislik)
Subject: Re: DBD::Oracle, tracing, and stored procedures...
Message-Id: <464427bf$0$28520$3b214f66@usenet.univie.ac.at>
Keywords: dbi dbd oracle tracing
In article <slrnf444qn.mki.urban@noisy.spielwiese.de>, ru@vakuum.de says...
>
>#======================================
># permutation 1:
>#======================================
>
>CODE>
>
>my $sql = qq{
> BEGIN
> sys.dbms_system.set_ev(46, 53017, 10046, 4, '');
> END;
>};
>$sql = $DBH->quote($sql);
This doesn't do any good. $DBH->quote returns one single string constant in
SQL syntax. Look closely at the error. Your statement starts with 'BEGIN ... instead of plain BEGIN ...
>my $rv = $DBH->do($sql);
>
>RESULT>
>
>DBD::Oracle::db do failed: ORA-00900: invalid SQL statement (DBD ERROR:
>OCIStmtExecute) [for Statement "'
> BEGIN
> sys.dbms_system.set_ev(46, 53017, 10046, 4, '''');
> END;
> '"] at ./trace.pl line 72.
Can't see any error in both the other permutations. I have called procedures
this way and it worked.
Cheers
Heinrich
--
Heinrich Mislik
Zentraler Informatikdienst der Universitaet Wien
A-1010 Wien, Universitaetsstrasse 7
Tel.: (+43 1) 4277-14056, Fax: (+43 1) 4277-9140
------------------------------
Date: 11 May 2007 00:28:31 -0700
From: Brian McCauley <nobull67@gmail.com>
Subject: Re: How to concatenate cookies
Message-Id: <1178868511.445458.288020@n59g2000hsh.googlegroups.com>
On 11 May, 06:09, dr_phill...@yahoo.com wrote:
> On May 10, 11:35 pm, "Mumia W." <paduille.4061.mumia.w
>
> +nos...@earthlink.net> wrote:
> > You can put several values into a single cookie like so:
>
> > my $cookie = $query->cookie(
> > -domain => $domainname,
> > -name => 'customfields',
> > -value => \@custom_fields
> > );
> > print $query->header(-cookie => $cookie);
>
> > Read the CGI docs again: perldoc CGI
>
> Thanks, but I am actually looking for each cookie to be seperate, so
> have multiple cookies in one variable $cookie. The docs says:
>
> you may concatenate the cookies together with ``; ''
>
> I am not sure what those characters mean ``; " ?
I'd guess they'd mean a literal semicolon (whereas you had a comma).
But one of my top rules of programming is "always use the most natural
representation of things". The most natural type of variable to
represent a list of things is an array (not a delimited string).
my @cookie_custom_fields;
for my $j ( 0 .. $#custom_fields ) {
push @cookie_custom_fields => $query->cookie(-domain=>
$domainname,
-name=>"custom$j",
-value=>"$in_field[$j]" );
}
print $query->header(-cookie=>\@cookie_custom_fields);
------------------------------
Date: Fri, 11 May 2007 15:26:08 +0800
From: "Ken Soon" <csoon@xilinx.com>
Subject: How to restart all hashes and arrays halfway through script
Message-Id: <f2160f$b9q1@cnn.xsj.xilinx.com>
Hi,
I am using dynamic arrays and hashes to store data. The names of the hashes
and arrays changes to a certain groups of names and there are alot of names.
Then i did some operations on this data with file::find, write to some files
and others....
However, as i continue on to another new operation on those hashes and
arrays, somehow all the values are gone or different (I'm not sure yet
whether is gone or different as I'm having trouble debugging to find out the
confirmed erroneous output)
Thus I am hoping if there such a thing to reset everything before i start on
that next operation. (as if i am restarting the script at that point)
Hmm all this sound abit weird though but i guess it is because haven't been
able to debug the problem.
hope my point is clear :X
------------------------------
Date: 11 May 2007 02:43:24 -0700
From: "sujay.tukai@gmail.com" <sujay.tukai@gmail.com>
Subject: Re: I'd like to create an array of unique values
Message-Id: <1178876603.949338.260100@n59g2000hsh.googlegroups.com>
On May 9, 8:29 pm, Mr P <MisterP...@gmail.com> wrote:
> Sounds just like keys %h don't it.
>
> Starting with
>
> $_ =
> "cat
> man
> dog
> mouse
> man
> man
> ";
>
> I want to end up with
>
> [cat man dog mouse]
>
> My approach is:
>
> my @s = split /\n/;
> # unique-afy it!
> my %s;
> @s{@s} = @s;
> @s = keys %s;
>
> My PREFERENCE is to not have to involve both a hash and an array, and
> also to not have to include a non-native lib module.
>
> Is there a syntax I can use to just work with the hash and populate
> the keys-only directly from the split? I don't really care what the
> values are. I don't even care if they are undef.
>
> Thank-You, Peristas,
>
> MP
I feel this is the shortest answer to ur query.
perl -e '$_ = "dog
man
dog
cat
mouse
man
man";
my %tmp; my @a;
@a = map {$tmp{$_}=$_ if(! $tmp{$_});} split("\n",$_);
print @a;'
------------------------------
Date: 11 May 2007 02:03:18 -0700
From: Klaus <klaus03@gmail.com>
Subject: Identify if a scalar is int, double or text
Message-Id: <1178874197.967635.164880@n59g2000hsh.googlegroups.com>
Hello,
I have a list of 4 scalars
my @L = (3, '3', 3.0, '3.0');
The first is obviously an int, the second is text, the third a double
and the last is text again.
I want to write a subroutine type_id which returns either 'int',
'double', 'text' (or '?') for each of the scalars, so that
print type_id($_), ' ' for (@L); print "\n";
results in the following output:
int text double text
I have found a solution where I use Devel::Peek, call Dump(), redirect
STDERR into an "in-memory" file ( \$data ) and analyse the "in-memory"
content:
$data =~ /^SV = IV(0x/ # for ints
$data =~ /^SV = NV(0x/ # for doubles
$data =~ /^SV = PV(0x/ # for text
but I wanted to know whether there is a better way.
**********************************************************
Here is my solution:
use strict;
use warnings;
use Devel::Peek;
print STDERR "Beginning of program\n";
my @L = (3, '3', 3.0, '3.0');
print type_id($_), ' ' for (@L);
print "\n";
print STDERR "End of program\n";
sub type_id {
# ============================
# At first I could not get the "in-memory"
# working. It took me a while before I
# found the all important documentation
# in perldoc -f open:
#
# [...] if you try to re-open STDOUT or
# STDERR as an "in memory" file, you have
# to close it first [...]
#
# As a consequence, a simple
# local *STDERR;
# open STDERR, '>', \$data;
# does not work.
#
# The following redirects STDERR into an
# "in-memory" file, but leaves STDERR
# closed on exit:
# local *STDERR = *STDERR;
# close STDERR;
# open STDERR, '>', \$data;
#
# so we have to dup STDERR first and
# restore STDERR manually at the end
# (...knowing that if the restore fails,
# we won't have STDERR anymore):
# ============================
# dup STDERR
open my $olderr, '>&', \*STDERR
or return "?002 [dup STDERR: $!]";
close STDERR
or return "?005 [close STDERR: $!]";
my $data = '';
open STDERR, '>', \$data;
Dump $_[0];
close STDERR;
# restore STDERR
open STDERR, '>&', $olderr or die;
if ($data =~ m{^SV = (.V)}) {
if ($1 eq 'IV') { return 'int' }
if ($1 eq 'NV') { return 'double' }
if ($1 eq 'PV') { return 'text' }
return "?020 [Invalid: SV = $1]";
}
return "?030 [Err: ".substr($data, 0, 12)."]";
}
--
Klaus
------------------------------
Date: 11 May 2007 07:10:06 GMT
From: tadmc@augustmail.com
Subject: Posting Guidelines for comp.lang.perl.misc ($Revision: 1.7 $)
Message-Id: <464416cd$0$3582$ae4e5890@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: 1.7 $)
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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The article at:
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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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Try doing a word-search in the standard docs for some words/phrases
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Search a Usenet archive
There are tens of thousands of Perl programmers. It is very likely
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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
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You may want to check in books or on web sites to see if you can
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There can be 200 messages in clpmisc in a single day. Nobody is going to
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For more information on choosing a Subject see "Choosing Good
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Do not say: I have variable with "foo\tbar" in it.
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or I have $var = <DATA> (and show the data line).
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Provide enough information
If you do the things in this item, you will have an Extremely Good
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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
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Ask the question here, get the answer here (maybe).
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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: 11 May 2007 00:18:34 -0700
From: Brian McCauley <nobull67@gmail.com>
Subject: Re: warnings dilemma
Message-Id: <1178867914.687057.127600@q75g2000hsh.googlegroups.com>
On 10 May, 22:05, kj <s...@987jk.com.invalid> wrote:
> In <1178818888.039832.23...@y5g2000hsa.googlegroups.com> Brian McCauley <nobul...@gmail.com> writes:
>
>
>
> >On May 10, 5:28 pm, kj <s...@987jk.com.invalid> wrote:
> >> I've read the PODs (warnings, perllexwarn) but I still don't know
> >> how to solve this problem. Here's a toy version of it.
>
> >> First some random module:
>
> >> # Foo.pm
> >> package Foo;
> >> use strict;
> >> use warnings;
>
> >> # calling foo() will result in an 'uninitialized' warning
> >> sub foo { my %h; exists $h{ $_[ 0 ] } }
> >> 1;
>
> >> __END__
>
> >> The function Foo::foo represents one of those situtations in which
> >> the author of the module, for whatever reason, has not taken steps
> >> to avoid a default warning.
> >So you don't like something about the way the module works.
>
> No, that's *not* the problem. The problem is that, as far as I
> can tell, there is no good way (either through code or through
> coding practices) to provide control over warnings to the calling
> script. Every alternative is deficient in one way or another.
Well, yes that's true. Nothing's perfect.
> >> Next, my script
>
> >> use strict;
> >> use Foo;
> >> { no warnings; Foo::foo(); }
> >> exit;
>
> >> Now, despite the "no warnings" in the script, when I run it I still
> >> get the "Use of initialized value in exists" warning.
> >That's right. That's the whole point of lexical scope.
>
> I disagree. I think a far more useful implementation of lexical
> control is to give each lexical scope the ability to control which
> warnings it allows to "bubble up" through it, in a way entirely
> analogous to the lexical control of fatal errors with eval.
The scope of control of fatal errors with eval() is _not_ lexical.
"Lexically scoped" describes the way "use warnings" or "use strict"
works now. What you want is the opposite of lexical scope - "dynamic
scope". This is what we had before we had lexical control with
local($^W) and what we still have with local($SIG{__WARN__}).
> E.g.
> under this version, code like this:
>
> if ( $verbose ) {
> use warnings;
> Foo::foo();
> }
> else {
> no warnings;
> Foo::foo();
> }
>
> would result in warnings only if $verbose is true. This is more
> useful than what we have now,
No it isn't. I'm not saying that the functionality you want would not
be useful sometimes but it would be usefull less often than what we
have now. I want to be able to suppress or promote warnings
selectively in _my_ code without an action-at-a-distance on other code
I happen to be calling.
> because it privileges scopes in
> proportion to their proximity to the top-level scope, as it should
> be.
I disagree. The descision as to which warning-causing circumstances
are expected and which are not (and which should be errors) belongs as
close as possible to where the expectation applies.
> I don't understand why it wasn't designed like this in the
> first place...
Because the designers agree with my way of thinking.
With perl 5.10's new caller() you could write a lexically scoped
pragma that actually had dynamically scoped effect because you have
access to all the lexical scope hints in all calling stack frames.
However the bit that's responsible for determining what warning
categories are enabled is not AFAIK replacable so you couldn't make
this selective by category. As I said before that probably doesn't
matter because for what you are trying to do filtering by category
does not make much sense anyhow.
------------------------------
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 425
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