Given a string of arbitrary (long) length that is known to comprise of a number of repetitions of an unknown length substring, (thought the last repetition my be incomplete), how to find that repeat sequence?

Eg. Given 'abcdabcdabcdabcdab' find 'abcd'.

Complications:

1. The first (shortest) repetition may not constitute the full repetition.

   Eg. In 'abcdabcdabceabcdabcdabceab'; 'abcd' is a false rep; the required rep is 'abcdabcdabce';

2. As mentioned, the last part of the string may be an incomplete repetition.

   The number of characters 'ignored' at the end of the string should be less than the length of the rep. Is is possible to code that into a regex? I guess it could just be checked afterwards.

I'm assuming that a regex solution would be possible, but I cannot wrap my brain around it today?

I'm pretty sure the answer is yes, but to be sure:

Are the references to anonymous code blocks in Perl always constant, because they are fixed at compile time?

  DB<115> sub tst (&) { print "$_[0]\n" }

  DB<116> tst {1,2,3,4} for 1..5
CODE(0xa396560)
CODE(0xa396560)
CODE(0xa396560)
CODE(0xa396560)
CODE(0xa396560)
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Is it reliably so? I took a look at B::Concised opcode output and as far as could see it seemed so...

Please note that it is not the case for anonymous hashes

  DB<118> sub tst (%) { print "$_[0]\n" }

  DB<119> tst {1,2,3,4} for 1..5
HASH(0xa3963f0)
HASH(0xa396940)
HASH(0xa396720)
HASH(0xa3966c0)
HASH(0xa3963f0)
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AFAIK, you can't use a placeholder with a SQL like statement. A coworker says you can. Can anyone confirm or deny it?

$query = 'select name from my_table where name like ?%';
my $sth = $dbh->prepare($query);
$sth->execute('Jo');
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Basically he is convinced that you can. Nothing I've shown him has convinced him otherwise. Hopefully some prince or princess of the Perl Monks can break this stalemate

UPDATE:

poj pointed out that I was incorrect. The percent sign belongs in the execute() not the prepare query.

$dsn = "dbi:Sybase:serverType=IQ:loginTimeout=240:server=$db_server_if
+c";
my $dbh = DBI->connect($dsn,
                         $self->get_db_username(),
                         $self->get_db_password(),
                         \%connect_options );

my $sqlA =<< "END_SQLA";
SELECT table_id
FROM   sys.systable
WHERE table_name like '${uc_table_name}%'
AND length(table_name) = $table_name_len
AND user_name(creator) = '$uc_schema'
END_SQLA

my $sthA = $dbh->prepare($sqlA);
$sthA->execute();

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How would do I access local __DATA__ inside a package?

Thanks

package Test;


sub run {

while(<Test::DATA>)
{
        print "$_\n";
}

}

__DATA__
1



#!/usr/bin/perl
use strict;
use warnings;

use Test;

Test::run();

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  my $myObjs = {
    alpha => re('^alpha(.*)'),
    beta => re('\d+'),
    #myOptionalField => re('^opt(.*)'),  #sometimes there is a "myOpti
+onalField", but sometimes there is not. What to do?
  };
  
  cmp_deeply(
    $response,
    {
      field1 => re('\d+'),
      field2 => 2,
      field3 => 1,
      objects => array_each($myObjs)
    },
    'testing for valid response structure'
  );
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I've been reading the Perl 5.18 delta, and now that smartmatch is both experimental and depreciated I'm in a bit of a muck. I have a big project that uses given/when quite heavily (28 givens, 85 whens).

What is the recommended way to fix this? I know I can turn off the warning, but I'd rather fix the code. The documentation says that given/when is subject to big changes and might even go away, so disabling the warning is only a temporary fix. An automatic fix would be nice, but I don't mind doing all the work by hand. I have a good test suite, so I'm not concerned about breaking things.

Mostly the given/whens look like this:

given($foo) {
  when('abc') {...}
  when(['foo', 'bar']) {...}
  default {...}
};
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This module was written to imitate the IO::Socket::INET API

So an obvious question is:

However, if I run the program with an --option that I haven't configured in the opt_spec function (of the sub command I'm invoking), it doesn't complain about an invalid option. I would expect it to do so. Instead it just quietly ignores that option.

I can't see anyway of configuring App::Cmd to complain about invalid options.

Is this possible, or is each sub-command expected to do the checking itself?

Thanks

#!/usr/bin/perl -w

use strict;
use IO::File;

use constant FILE => 'D:\ps-scripts\DirectX.log';
use constant FIND => 'eroare';

IO::File->input_record_separator(FIND);

my $fh = IO::File->new(FILE, O_RDONLY)
  or die 'Could not open file ', FILE, ": $!";

$fh->getline;  #fast forward to the first match

#print each occurence in the file
print IO::File->input_record_separator
  while $fh->getline;

$fh->close;
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Hi monks,

I was reading SDL::Manual, and after having followed instructions for installation (with cpan), I tried the first examples.

Creating a window works. I get a black window with this basic code:

use strict;
use warnings;
use SDL;
use SDLx::App;
my $app = SDLx::App->new(w => 400, h => 400);
sleep(4);
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But if I try to draw something, such as a line (as in the book):

use strict;
use warnings;
use SDL;
use SDLx::App;
my $app = SDLx::App->new(w => 400, h => 400, d => 32);
$app->draw_line( [200, 20], [20, 200], [255, 255, 0, 255] );

$app->update();
sleep(4);
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Then the screen stays totally black. No error message, no warning. I guess something is wrong with the installation of the library. Any idea on how I could fix that?

UPDATE: It seems that I can make things appear when I call $app->run();

It's not what is in the manual, though. And when I call this, I can't stop the processus anymore, not even with Ctrl-C :/

Update: I spent so long tracking this down that when I discovered the cause I posted before doing the proper checks which show it is fixed in later builds. My apologies.

Any explanations for this?

C:\test>perl
$a = chr(0); $a x= 2**31;
substr( $a, 0, 2**16 ) =~ tr[\0][\1];
substr( $a, 2**16, 2**16 ) =~ tr[\0][\1];
^Z
substr outside of string at - line 2.
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Recently, I've been thinking about a really, really minor perl issue: what's the best way to format your script's main routine? I'd also always wondered how you were supposed to unit-test the main routine in your script. I recently came up with an idea (inspired by a brian_d_foy article) that answers both questions for me.

When I first started coding, I just put everything in my main routine at top level-- in global scope. My scripts looked something like this (translated from perl 4):

#!/usr/bin/env perl

use strict;
use warnings;

# Script variables
our $Foo = 'bar';

# Main routine
my ($name, $greeted) = @ARGV;

$name //= 'Horace!';
$greeted //= 'world';
say_hello($greeted);

# Subroutines
sub say_hello {
    my ($name) = @_;
    
    print "Hello $name\n";
}
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Twitter recently got rid of the ability to get search results as an RSS as part of their API update of 11 June 2013.

I found those feeds rather useful, so I made a little screen scraper that reimplements the functionality without needing to auth against their API (it just pulls the results out of the web search page). I guess this will be good for a while longer, like enough time to switch to statusnet, identica, or whatever.

It might be of use to some others in the monastry and illustrates the power of HTML::TreeBuilder::XPath.