If
you have a question on how to do something in Perl, or
you need a Perl solution to an actual real-life problem, or
you're unsure why something you've tried just isn't working...
then this section is the place to ask.
However, you might consider asking in the chatterbox first (if you're a
registered user). The response time tends to be quicker, and if it turns
out that the problem/solutions are too much for the cb to handle, the
kind monks will be sure to direct you here.
I have tried to download the 8mb index.all file from the Gutenburg Project website with LWP::UserAgent but it only gets around 5mb.
With wget I gets the full file, is there some limit in LWP? I have tried LWP::Agent many times and it gets between 4mb-5.2mb.
my $url = 'https://www.gutenberg.org/dirs/GUTINDEX.ALL';
my $file = '/home/philip/APPLICATIONS/GUTINDEX.ALL';
say $url;
my $browser = LWP::UserAgent->new();
my $response = $browser->get($url);
open my $fp,">",$file || die "Error saving book $!\n";
print $fp $response->content();
close $fp;
I visited the Rosetta Code, for solution to a problem in a language, which both don't matter here; then checked Perl solution there; then, out of idle curiosity, as it's usual with time wasting e.g. browsing dictionaries, clicked for one more task; and -- I swear (and don't know what in its title attracted me)-- at exactly the 3d task I found a Perl solution:
Out of ALL contestants, the task was misread to include 5-letter words, and even then, the algorithm is broken as it doesn't contain e.g. "crises crisis" pair, etc. So sad :-(. Village idiot, our Perl, no less. No, I don't have editing rights there, nor did I find in page's history how/when it was added.
However, I've been surprised to find it hard and not obvious (to me), how to match the solution's speed/memory. Presumably, if corrected they'd stay the same or close. My initial attempts with e.g. grep/map/split/regexes or what not -- they all were worse.
Finally, here's my solution (under Strawberry):
use strict;
use warnings;
sub memory { qx( tasklist /nh /fi "PID eq $$" ) =~ m[(\S+ K)$] }
use Time::HiRes 'time';
my $t = time;
my ( @a, %h );
open my $fh, '<:raw', 'unixdict.txt' or die;
while ( <$fh> ) {
next unless length > 6;
chomp;
( -1 != index $_, 'e' ) ? ( push @a, $_ ) :
( -1 != index $_, 'i' ) ? ( $h{ $_ } = 1 ) : 1
}
close $fh;
my ( $s, $i ) = '';
exists $h{ $i = tr/e/i/r }
and $s .= sprintf "%30s %s\n", $_, $i
for @a;
print time - $t, "\n";
print memory, "\n";
print $s;
It's on average "0.018 s, 10,100 K" vs "0.033 s, 11,100 K" of similarly modified (but still unfixed) original. Not that "performance" matters for the task, how ever ridiculous this achievement is.
I'm trying to optimize a regex using the SKIP and MARK verbs, and not understanding how they should be properly used together. Sadly, the documentation provides no examples, and doesn't seem to rigorously define its terms:
"(*MARK:*NAME*)" "(*:*NAME*)"
This zero-width pattern can be used to mark the point reached in
a string when a certain part of the pattern has been successfully
matched. This mark may be given a name. A later "(*SKIP)" pattern
will then skip forward to that point if backtracked into on
failure.
to capture the b, yet it again captures the second a.
Perhaps subpatterns such as (?!...) don't share marks with the main pattern? The slightly more verbose pcre doc seems to say that. But then this should work:
I've been installing packages via cpan without any problems. Then I had some failures with Perl using the wrong compiler command and options, so I corrected that, got out of cpan and then back in. Ever since I got back in, nothing will install now. I keep getting the following error for everything:
gpg run was failing, cannot continue: "/opt/freeware/bin/gpg" --verify
+ --batch --no-tty --output "/tmp/CHECKSUMS-eMRO/CHECKSUMS.6095688" "/
+usr/local/src/perl/.cpan/sources/authors/id/S/ST/STRO/CHECKSUMS" 2> "
+/dev/null"
I didn't change anything for gpg. It was working fine earlier, but it isn't now. One thing that I did was install the latest CPAN. I've done a number of Google searches and can't find anything helpful. I've got a long list of packages that need to be installed and now I'm at a complete standstill. Does anyone have any ideas on what I need to check/change? Thanks.
I am analysing a LibreOffice Calc spreadsheet and need to manipulate a date field.
The values are seemingly read in OK but the parsing is not working somehow.
Code replicated below - ignore the positioning of the use statements, just trying to fathom out what is going on/how to get the result that I need and there are several spurious statements present that can probably be/will be redacted, including the print ones that I am using for monitoring purposes. The main If...then...else is still present due to having read in different formats previously (as alluded to) and finding that strptime gave different returns than I was expecting, hence the extra call to ParseDate
Date format used is in UK style dd/mm/YYYY
The date of 31/08/2024 works OK when read in
The data of 01/09/2024 (ie the next calendar day) gives gibberish - with the day coming out as 09 instead of 1, month as 01 instead of 9 and the year as 124.
Note that I have tried specifying the Zone in the ParseDate call but when I set it to GMT, the perl throws up an error about using barewords and using the directive of "ZONE => " does not help
I have tried various parsing calls using different utilities but I can't find one that behaves itself and consistently provides the correct answer or needs the parameters in a specific format (not impossible to do, just seems to be extra, unnecessary work)
I have also tried stepping through the relevant calls (eg strptime) at debugging run time but my perl is not good enough to decipher what is going on with the pattern matching algorithm
Therefore - any recommendations to code alterations/other better-behaved utilities would be gratefully received.
Also - anyone know why ParseDate returns a month one less than it should ?
many thanks
ADB
... code is read into $lCell variable ...
$lCell .= ""; # Force read detail into a string format, just in cas
+e (as I have seen ... !)
use Date::Parse;
use Date::Manip;
print ("$lCell ...\t");
my @ttt = strptime ($lCell);
my $yyy = ParseDate ($lCell,,);
#print "ADB $yyy...\n";
if ($yyy ne "")
{
# Format originally read was in the format 2024-08-09 before c
+onverting to string format
#code.
$lDay = substr($yyy,6,2);
$lMonth = substr($yyy,4,2);
$lYear = substr($yyy,0,4);
}
else
{
# Format was originally 16-08-2024 or similar
$lDay = $ttt[5];
# NOTE HERE that the month range in some perl modules has a ra
+nge 0..1 NOT 1..12, so adjust
$lMonth = $ttt[4] +1;
$lYear = $ttt[3];
}
I tested on two different installations that the debugger is activating a bunch of features when using it interactively.
I suppose it's doing a use VERSION internally activating features
It's kind of surprising because I provided a -e and not a -E in the prompt.
Is this documented behavior and if not shouldn't it be?
~$ perl -de0
Loading DB routines from perl5db.pl version 1.77
Editor support available.
Enter h or 'h h' for help, or 'man perldebug' for more help.
main::(-e:1): 0
DB<1> p $]
5.038002
DB<2> use B::Deparse
DB<3> p B::Deparse->new->coderef2text(sub{})
{
use feature 'current_sub', 'bitwise', 'evalbytes', 'fc', 'isa', 'm
+odule_true', 'postderef_qq', 'say', 'signatures', 'state', 'unicode_s
+trings', 'unicode_eval';
}
DB<4>
This is what happened. I downloaded the MSI installer for Perl 5.40.2.1 (2025-05-11). A fresh new Perl! Oh joy, oh excitement! oh ...NO. I did something bad. I configured the MSI installer to unpack Strawberry over my existing Strawberry installation (which was v5.32.1). Now I get various errors including the following:
perl -MWin32::Clipboard -e1
-e: Perl lib version (5.32.1) doesn't match executable 'C:\perl\perl\bin\perl.exe' version (5.40.2) at C:/perl/perl/lib/Config.pm line 62.
Pretty soon after this crippling of Strawberry on my system drive I installed the portable Strawberry onto a USB flash drive. I've made mention of that installation in other recent postings. Now it's working fine, BTW. But what I want to ask, what I am seeking, is: Is there any hope for my previous existing StrawberryPerl, or is it hopelessly trashed? I installed many modules from CPAN with that Strawberry, I'd really like to retrieve all the work that's gone into that installation.
The only thing I've thought of is going backwards and installing the older, previous Strawberry release on top of the new, broken one. I think that if I do so, perl will run. But not much else to be gained, perhaps.
If nothing else gets accomplished by this posting, maybe someone who is about to do what did will read it and be warned to NOT DO THAT.
Jun 09, 2025 at 19:12 UTC
A just machine to make big decisions
Programmed by fellows (and gals) with compassion and vision
We'll be clean when their work is done
We'll be eternally free yes, and eternally young Donald Fagen —> I.G.Y. (Slightly modified for inclusiveness)
First, although strawberry is in the software center and allowed to be installed, cpan is not working due to corporate policy
Second, regarding INC
@inc:
Have \progra3\appv\69bae71\f2241d~1\root\perl\lib
Want \strprl40.501\perl\lib
Your perl and your Config.pm seem to have different ideas about the
architecture they are running on.
Perl thinks: [lib]
Config says: [MSWin32-x64-multi-thread]
This may or may not cause problems. Please check your installation of
+perl
if you have problems building this extension.
Generating a gmake-style Makefile
Nevertheless, for many modules this is not an issue and the module installs and is usable fine.
Fourth, for many (not just Win32 OLE as here) I get a weird install error:
gmake install
"C:\ProgramData\AppV\69BAE760-7169-4C2A-B9C9-F1E18DDC5EAC\F2241D52-0D9
+8-449E-B93D-6ABC6A7CB779\root\perl\bin\perl.exe" -MExtUtils::Command:
+:MM -e cp_nonempty -- OLE.bs blib\arch\auto\Win32\OLE\OLE.bs 644
Files found in blib\arch: installing files in blib\lib into architectu
+re dependent library tree
Installing C:\Strprl40.501\perl\site\lib\auto\Win32\OLE\OLE.xs.dll
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+!!
ERROR: Cannot copy 'blib\arch\auto\Win32\OLE\OLE.xs.dll' to 'C:\Strprl
+40.501\perl\site\lib\auto\Win32\OLE\OLE.xs.dll': No such file or dire
+ctory
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+!!
at -e line 1.
gmake: *** [makefile:737: pure_site_install] Error 2
Volume in drive C has no label.
Volume Serial Number is F2DC-59D5
Directory of c:\Users\alexspy\FAILEDINSTALL\Win32-OLE-0.1713\blib\arch
+\auto\Win32\OLE
06/06/2025 16:32
.
06/06/2025 16:31 ..
06/06/2025 16:31 0 .exists
06/06/2025 16:32 110,592 OLE.xs.dll
2 File(s) 110,592 bytes
2 Dir(s) 164,110,532,608 bytes free
So the dll is there.
Maybe the target directory is the problem?
dir C:\Strprl40.501\perl\site\lib\auto\Win32\OLE
Volume in drive C has no label.
Volume Serial Number is F2DC-59D5
Directory of C:\Strprl40.501\perl\site\lib\auto\Win32\OLE
06/06/2025 16:33
.
06/06/2025 16:33 ..
0 File(s) 0 bytes
2 Dir(s) 164,110,528,512 bytes free
c:\Users\alexspy\FAILEDINSTALL\Win32-OLE-0.1713>copy c:\Users\alexspy\
+FAILEDINSTALL\Win32-OLE-0.1713\blib\arch\auto\Win32\OLE\OLE.xs.dll C:
+\Strprl40.501\perl\site\lib\auto\Win32\OLE
The system cannot find the path specified.
0 file(s) copied.
Does this make sense??
For completeness, here are the steps before the gmake that fails
Win32-OLE-0.1713>perl Makefile.PL
Have \progra3\appv\69bae71\f2241d~1\root\perl\lib
Want \strprl40.501\perl\lib
Your perl and your Config.pm seem to have different ideas about the
architecture they are running on.
Perl thinks: [lib]
Config says: [MSWin32-x64-multi-thread]
This may or may not cause problems. Please check your installation of
+perl
if you have problems building this extension.
Generating a gmake-style Makefile
Writing Makefile for Win32::OLE
Writing MYMETA.yml and MYMETA.json
Last, Tk is another modules that has an issue and gives errors. I see there is a patch, but I think this only works via cpan. Do we have a Tk modules that can be built via Makefile/gmake?
I am extracting keyword and definition pairs from a large html document with HTML::Treebuilder and HTML::Element.
After parsing the html string and dumping nodes, I find that the <br/> tag is missing.
How could I prevent that>?
use HTML::TreeBuilder 5 -weak;
my $tree = HTML::TreeBuilder->new;
# HTML given is read from a file in UTF-8 format. Using parse_file
+ returns garbled characters.
my $html = shift;
# The next 2 lines are added to see whether it would impact losing
+ <br/> tags
$tree->no_space_compacting(1);
$tree->ignore_unknown(0);
$tree->parse( $html );
$tree->eof();
...
...
$Definition = $DefinitionNode->as_HTML('<>&');
