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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. Post a new question!
However, you might consider asking in the chatterbox first (if you're a
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out that the problem/solutions are too much for the cb to handle, the
kind monks will be sure to direct you here.
I am trying to improve the error handling of my application that uses SQLite. I have noticed that the following script is not producing an error, no matter what $database is (empty, a non existing database name, etc.). However, if $database does not exist I would have expected to see an error. This forces me to first check for the existence of $database. Is this a feature?
use DBI;
use strict;
my $driver = "SQLite";
my $database = "";
my $dsn = "DBI:$driver:dbname=$database";
my $userid = "";
my $password = "";
my $dbh = DBI->connect($dsn, $userid, $password, { RaiseError => 1 })
or die $DBI::errstr;
print "Opened database successfully\n";
Hi folks. I work at a company where I don't normally do scripting. I tend to use Perl for like 3 days for some one off scripting need, and then promptly forget everything I learned. I was hoping someone could do this reg exp faster.
Say I have a an automatically dumped command line like:
Since it's difficult to parse what's really going on when it's all a single line, I instead would like to create a script that would take this command line as input and effectively print out something like the below in a kind of tree format:
Can someone help me get started on the most efficient reg exps to do this? There are certain anchors I can see in which to key off of in terms of knowing when to tab, but it's not consistent. For instance, can't always use the "-" reliably to know when to tab over.
when i launch the my program, occasionally i receive this message:
Can't call method "rows" on an undefined value at download_and_parse_v3.pl line 81.
So, because i want the program goes on even on this error, i tried this in replace of the above instruction:
push @tbl, [ @$_ ] for $table->rows or warn " ERRORE $hname $chin ";
where $hname and $chin are variables in the program that can help me understood the reason of the error.
At this point i thought that i had the above phrase instead the "Can't call method rows..."
but i alwais receive the same message.
Where is my mistake?
Thanks
Hello, Monks. I'm hoping that you can help me with what is probably quite a simple problem, but which is completely stumping me!
I'm trying to work with text files which are fairly disorganized in terms of structure, and which have been stored in a hash. What I want from each file is to extract the line of text which begins "title:#" and ends with a "#" and store this text in a scalar to be used later.
The problem arises because, within some of the text files, there are multiple lines which begin and end with "title#" and "#" respectively. What distinguishes the "titles" I want is that they only ever appear in each text file once, whereas the "titles" I do not want appear at least twice (but sometimes three or four times) in the same text file.
So this is the basic script that I am using, which prints out all the titles
use warnings;
use strict;
my %mycorpus = (
a => "<blah blah blah
blah
title:#this is text I want 1#
blah blah blah",
b => "blah
title:#this is text I do not want# blah
title:#this is text I want 2#
blah
title:#this is text I do not want#
blah",
c => "blah blah
title:#this is text I want 3#
title:#this is text I do not want#
title:#this is text I do not want#
title:#this is text I do not want#
blah",
);
foreach my $filename (sort keys %mycorpus) {
my $titles = '';
while ($mycorpus{$filename} =~ /title:#(.*?)#/g){
$titles = $1;
print "$titles \n";
}
}
In the second example searching for "cgi" returns the metadata for "CGI"
but both module and filename keys contain "cgi" and are not valid as a
package or file for the "CGI" distribution?
Hello, i am hoping you can help me. I am using the Win32::GUI module and i have a listview added. I am trying to catch a button-click on a column name so i can sort on that column. I am looking through the documentation but i can't find anything.
Here is what i have so far:
use strict;
use warnings;
use Win32::GUI();
use DBI;
my $mw = Win32::GUI::Window->new(
-text => "View",
-size => [ 550, 500 ],
-pos => [ 200, 200 ],
);
sub mw_Terminate { return -1 }
my $lv = $mw->AddListView(
-pos => [ 20, 20 ],
-size => [ 400, 400 ],
-gridlines => 1
);
$lv->InsertColumn( -item => 0, -text => "PID", -width => 50);
$lv->InsertColumn( -item => 1, -text => "Name", -width => 100);
$lv->InsertColumn( -item => 2, -text => "Address", -width => 100);
$lv->InsertColumn( -item => 3, -text => "Salary", -width => 100);
my $dbfile = 'C:/code/lqs.db';
my $dbh = DBI->connect("dbi:SQLite:dbname=$dbfile","","");
my $stmt = qq(select id,name,address,salary from deliver order by sala
+ry desc);
my $sth = $dbh->prepare($stmt);
$sth->execute;
while(my @row = $sth->fetchrow_array()){
$lv->InsertItem(-text => [$row[0],$row[1],$row[2],$row[3]]);
}
$mw->Show;
Win32::GUI::Dialog();
Dear all,
when I run the below code,I got this error
Not a HASH reference at mojo.pl line 112.
which refer the last line when I print it
How to fix it please??
I want to print the sample size (3,117) and other attributes
Thanks in advance
=========================
This is minor but I find it annoying. When I print 80 characters and then a newline on the Windows command prompt it prints a blank line after the line. The Linux command prompt doesn't do this. My workaround on Windows has been to only print 79 characters per line. My question is why? I don't know how to print a newline from a batch file or I would test it.
use warnings;
use strict;
print "-"x79,"\n";
print "1\n";
print "-"x80,"\n";
print "2\n";
print "-"x80;
print "3\n";
__DATA__
--redirected to a file in Windows.
----------------------------------------------------------------------
+---------
1
----------------------------------------------------------------------
+----------
2
----------------------------------------------------------------------
+----------3
--appearance from Windows command line.
----------------------------------------------------------------------
+---------
1
----------------------------------------------------------------------
+----------
2
----------------------------------------------------------------------
+----------
3
--appearance from Linux command line.
----------------------------------------------------------------------
+---------
1
----------------------------------------------------------------------
+----------
2
----------------------------------------------------------------------
+----------
3
and I want to produce a 'quoted' comma separated list (a bit like CSV) of the names, i.e.:
'Adam','Bob','Cat'
can anyone offer more concise/efficient/elegant ways of doing it than this kind of approach, which does work, and is pretty concise, but ain't pretty:
$csv .= ",'$AoH[$_]{name}'" for (0..$#AoH);
$csv =~ s/^,//;
Update: If there are no names (i.e. @AoH is empty), the output should be:
''
i.e. 2 single quotes, but my solution above doesn't meet that requirement (I've replied to Rolf below with some which do, though).
