RE: Cookies
On Wed, 17 Sep 2003 20:33:00 -0800, Alejandro Chavarria - CyPage [EMAIL PROTECTED] wrote: Hey, I have a script and I want to allow an administrator log on to it. Once logged in they can change things... etc. Basically stuff I don't want other people to be able to do. I have decided that cookies is the best way to go. I've been looking and looking on the internet for a way to add a logout button in the script that will delete the cookie that has the username and password so they are essentially logged out. I have read that you can fill in the expires field in with 1. a date in the past (ie. -1d) or 2. the word now. I have heard about problems with both these methods. What do you suggest? In general I would reset the cookie to the empty string with no expiration date, and then on the other end your check should be that the cookie exists *and* has a correct value. Then make the correct value very hard (because nothing is 100% secure) to figure out how to generate. In other words hash it with a secret key or some such that only the server has. So the cookie exists but the check fails, and as soon as the session ends the cookie is no longer stored. http://danconia.org -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: list-parsing problem
Two dimensional hash perhaps? Where the first column is the first dimension and the
second is, well, the second.
E.g.
while(FH)
{
($col1, $col2) = split(/$delimeter/, chomp($_));
$blah{$col1}{$col2} = 1;
}
Hope this helps.
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Re: problems with DBD::mysql
Erwin Van Kouteren wrote: Hi there, I'm having problems with th einstallation of the module DBD::mysql. When giving the command: perl Makefile.PL the script gives error messages about de mysql_config file. (no such file). Can anyone help me any further on this matter? Thanks, Erwin This is a common problem. If you can install mysql from the source then this problem will not occur Since the the mysql header files will be installed by the source. Or else, You can just untar the source in some temporary area find mysql.h ( I dont remember exactly but must be the same file ) in the directory and change the Makefile of DBD::mysql to include that directory Hope that helps Ram -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: list-parsing problem
Thanks Michel, I found it! But I just have one question before trying it out. Isn't the key order in a hash randomised, which in this case means I wouldn't get first column in numerical order as I wanted? Marcus On Thu, 2003-09-18 at 10:31, EUROSPACE SZARINDAR wrote: Hi Marcus Just look at the perldoc perlreftut. What you are looking for is the exact exemple of the paper. Michel -Message d'origine- De: Marcus Claesson [mailto:[EMAIL PROTECTED] Date: jeudi 18 septembre 2003 11:26 : [EMAIL PROTECTED] Cc: [EMAIL PROTECTED]; [EMAIL PROTECTED] Objet: list-parsing problem Hi People, I have a silly little list-parsing problem that I can't get my head around, and I'm sure some of you have come across it before. I have a list like this: 1 a 2 b 2 c 3 a 4 d 4 d 4 e 4 f 5 g and I want to make the first column non-redundant and collect the second column values on the same line, like this: 1 a 2 b,c 3 a 4 d,e,f 5 g Please note that line 4 only has one 'd'. I've tried with both hashes and arrays (don't want to confuse you so I won't display them here), but nothing really works... I would really appreciate any help! Marcus -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: list-parsing problem
Marcus Claesson [EMAIL PROTECTED] wrote : : I have a silly little list-parsing problem that I can't get : my head around, and I'm sure some of you have come across : it before. : : I have a list like this: : : 1 a : 2 b : 2 c : 3 a : 4 d : 4 d : 4 e : 4 f : 5 g : : and I want to make the first column non-redundant and : collect the second column values on the same line, like : this: : : 1 a : 2 b,c : 3 a : 4 d,e,f : 5 g : : Please note that line 4 only has one 'd'. What order should each column be in? The input order or some kind of sort order? Or does order matter? HTH, Charles K. Clarkson -- Head Bottle Washer, Clarkson Energy Homes, Inc. Mobile Home Specialists 254 968-8328 -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: list-parsing problem
Homework's sorted ;)! Thanks a lot Thomas, it worked fine!
Marcus
On Thu, 2003-09-18 at 10:41, Thomas Btzler wrote:
Marcus Claesson [mailto:[EMAIL PROTECTED] asked:
I have a silly little list-parsing problem that I can't get my head
around, and I'm sure some of you have come across it before.
Sure. Looks like homework ;-)
HTH,
Thomas
#!/usr/bin/perl -w
use strict;
my %unique;
while( DATA ){
my( $key, $value ) = split;
$unique{$key}-{$value}++
}
foreach my $key ( sort keys %unique ){
print $key: . join( , , sort keys %{$unique{$key}} ) . \n;
}
__DATA__
1 a
2 b
2 c
3 a
4 d
4 d
4 e
4 f
5 g
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RE: list-parsing problem
Marcus Claesson [EMAIL PROTECTED] : : But I just have one question before trying it out. : Isn't the key order in a hash randomised, which in : this case means I wouldn't get first column in : numerical order as I wanted? You didn't state what order in the problem not did you say that the first column would always be numeric. You didn't state it for the second column either. Charles K. Clarkson -- Head Bottle Washer, Clarkson Energy Homes, Inc. Mobile Home Specialists 254 968-8328 -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: list-parsing problem
On Thursday 18 Sep 2003 10:26 am, Marcus Claesson wrote:
Hi People,
I have a silly little list-parsing problem that I can't get my head
around, and I'm sure some of you have come across it before.
I have a list like this:
1 a
2 b
2 c
3 a
4 d
4 d
4 e
4 f
5 g
and I want to make the first column non-redundant and collect the second
column values on the same line, like this:
1 a
2 b,c
3 a
4 d,e,f
5 g
Please note that line 4 only has one 'd'.
I've tried with both hashes and arrays (don't want to confuse you so I
won't display them here), but nothing really works...
I would really appreciate any help!
Marcus
Hi Marcus,
Hows about something like:
my @f=(1 a,2 b,2 c,
3 a,4 d,4 d,
4 e,4 f,5 g);
my %cols=();
foreach(@f) {
my ($col1,$col2)=split(/ */,$_);
$cols{$col1}.=$col2;
}
foreach (sort keys %cols) {
print join(,,split('',$cols{$_})),\n;
}
If you actually want the commas in the scripts, you'll need to do it either
inside the first loop, or have a seperate loop just after.
Gary
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Recursively scanning a directory on Mac OS X for size Timestap
Hi,
I'm doing the following and the purpose is to genrate a HTML log file. But
the script says Can not apply stat : No such file or directory found
Can someone plz tell me where I'm going wrong ?
use File::Find;
use File::stat;
open (OUT,./out.html);
$Root = $ARGV[0];
print $Root;
my $var;
print OUT 'html
head
meta http-equiv=Content-Language content=en-us
meta http-equiv=Content-Type content=text/html; charset=windows-1252
meta name=GENERATOR content=Microsoft FrontPage 4.0
meta name=ProgId content=FrontPage.Editor.Document
titlePath of File/title
/head
body
table border=1 width=106%
tr
td width=20% align=center bgcolor=#00bPath of
File/b/td
td width=20% align=center bgcolor=#00bFile
Version/b/td
td width=20% align=center bgcolor=#00bBuild
Number/b/td
td width=20% align=center bgcolor=#00bSize on
Disk/b/td
td width=20% align=center bgcolor=#00bTimestamp/b/td
/tr';
find (\wanted,$Root);
print OUT ' /table
pnbsp;/p
/body
/html';
sub wanted()
{
if (-d $File::Find::name)
{
return;
}
$file = $File::Find::name;
$file =~ s/\//\\/g;
$st = stat($file);
$size = $st-size;
$size = ($size/1024).KB ($size bytes);
$time = scalar localtime $st-mtime;
print OUT '
tr
td width=20% align=center bgcolor=#CC'.$file.'/td
td width=20% align=center bgcolor=#CCNot Available/td
td width=20% align=center bgcolor=#CCNot Available/td
td width=20% align=center bgcolor=#CC'.$size.'/td
td width=20% align=center bgcolor=#CC'.$time.'/td
/tr';
Regards,
Shishir Saxena
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recursively finding file size/timestamp on a Mac / Solaris
Hi,
This is wat I'm doing... but its not working :-(
find (\wanted,$Root);
print OUT ' /table
pnbsp;/p
/body
/html';
sub wanted()
{
if (-d $File::Find::name)
{
return;
}
$file = $File::Find::name;
$file =~ s/\//\\/g;
$st = stat($file);
$size = $st-size;
$size = ($size/1024).KB ($size bytes);
$time = scalar localtime $st-mtime;
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assign new letter to drive in Win32?
Hi... I was hoping to use Perl to invoke the MS utility diskpart to script some disk management, especially in order to rename drives and partitions. Unfortunately, diskpart is an XP utility-- on Win2K, I can use diskpart to strip the letter from the drive, but attempting to assign a new letter yields an error msg. that this operation is not supported on your version of Windows. Does anyone know if Perl is capable of stripping/assigning drive letters on Windows 2000? And if so, how? Or where I could read more? -Chris PS Any other pointers to Perl-on-Windows would be helpful-- I have Learning Perl on Win32 Systems, but I'm a Windows newbie and further information is always helpful... -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
DBD:Pg place holder errors
Howdy:
I have a script where I connect from Oracle 9 to
PostgreSQL 7.2.x and insert new records. It seems
to work for about 200 or so records, but, fails
(I was able to capture this message)
[error]
Uncaught exception from user code:
Placeholder :0 invalid, placeholders must be = 1 at
/usr/lib/perl5/site_p
erl/5.6.0/i386-linux/DBD/Pg.pm line 129.
DBD::Pg::db::prepare('DBI::db=HASH(0x83d88a0)', 'insert into
sys_ed_inp (^
JMBR_ID,^JCODE,^JPROC_1,^JPROC_2,^JPROC_3,^JD...', undef) called at
/usr/lib/perl5
/site_perl/5.6.0/i386-linux/DBI.pm line 1212
DBD::_::db::do('DBI::db=HASH(0x83d88a0)', 'insert into sys_ed_inp
(^JMBR_I
D,^JCODE,^JPROC_1,^JPROC_2,^JPROC_3,^JD...') called at
./insert_sys_ed_inp.pl line
95
Database handle destroyed without explicit disconnect at
/usr/lib/perl5/site_perl/
5.6.0/i386-linux/DBD/Pg.pm line 129.
[/error]
What is this talking about? I'm not sure I understand why it
failed after so many records. I *thought* it could be a record
was off or a column had some odd character or whatever, but
perhaps I don't see that? The table should accept NULLs by
default and the table structure on both DBs are the same.
This is the code
[snip code]
#!/usr/bin/perl -w
# created 17 Sep 03
# script to connect from Oracle via DBI to
# PostgreSQL and insert records into a table
#
use POSIX 'strftime';
use strict;
use warnings;
use diagnostics;
use DBI;
my $host='local';
my $sid='jessupic';
my $dbname='o_testdb';
my $username='joe';
my $password='joe_passwd';
my $datestr=strftime '%d%m%Y',localtime;
# connection options either works
my $dbh = DBI-connect(dbi:Oracle:host=$host;sid=$sid, $username,
$password, { R
aiseError = 1 }) or die Can not connect: $!;
if (!defined($dbh)) {exit;}
# test the SQL
# don't use semi-colons? wonder why ...
#
print \nthis is for SYS_ED_INP table\n\n;
my $sql =
SELECT
MBR_ID,
CODE,
PROC_1,
PROC_2,
PROC_3,
DIAG_1,
DIAG_2,
DIAG_3,
DIAG_4,
DIAG_5,
FROM_DT,
THRU_DT,
BILLINGPROVIDERNUM,
BILLINGPROVIDERNAME,
DIAGNOSISDESCRIPTION,
ADDED,
ID,
PRODUCT
from
SYS_ED_INP
;
# test the sql and prepare to use
# for Oracle
my $sth = $dbh-prepare($sql) or die Error = , DBI::errstr;
unless ($sth-execute) {
print\n\tExecute failed for stmt:\n\t$sql\nError = , DBI::errstr;
$sth-finish;
$dbh-disconnect;
die \n\t\tClean up finished\n;
}
print \nThis is to be inserted into PostgreSQL ...\n\n;
print \nThis is the build time $datestr ...\n\n;
while (my (
$MBR_ID,
$CODE,
$PROC_1,
$PROC_2,
$PROC_3,
$DIAG_1,
$DIAG_2,
$DIAG_3,
$DIAG_4,
$DIAG_5,
$FROM_DT,
$THRU_DT,
$BILLINGPROVIDERNUM,
$BILLINGPROVIDERNAME,
$DIAGNOSISDESCRIPTION,
$ADDED,
$ID,
$PRODUCT
) =$sth-fetchrow) {
my $dbh_p=DBI-connect('dbi:Pg:dbname=test_db', 'joe')
or die Can not connect: $!;
$dbh_p-do(insert into sys_ed_inp (
MBR_ID,
CODE,
PROC_1,
PROC_2,
PROC_3,
DIAG_1,
DIAG_2,
DIAG_3,
DIAG_4,
DIAG_5,
FROM_DT,
THRU_DT,
BILLINGPROVIDERNUM,
BILLINGPROVIDERNAME,
DIAGNOSISDESCRIPTION,
ADDED,
ID,
PRODUCT
) values (
'$MBR_ID',
'$CODE',
'$PROC_1',
'$PROC_2',
'$PROC_3',
'$DIAG_1',
'$DIAG_2',
'$DIAG_3',
'$DIAG_4',
'$DIAG_5',
'$FROM_DT',
'$THRU_DT',
'$BILLINGPROVIDERNUM',
'$BILLINGPROVIDERNAME',
'$DIAGNOSISDESCRIPTION',
'$ADDED',
'$ID',
'$PRODUCT') );
$dbh_p-disconnect;
}
print done with the sys_ed_inp program.\n\n;
$dbh-disconnect;
[/snip code]
Suggestions? TIA!
-X
instance variables?
Hi all,
I stumbled across something called BlueJ which provides a user-friendly
graphical environment in which to learn OO-programming, Java-style. I think
this is a great parallel universe to go along with the Perl Objects book.
I started re-writing one of the first exercises as a Perl package:
[question follows below]
package TicketMachine;
# etc.
=head1 DESCRIPTION
TicketMachine models a naive ticket machine that issues
flat-fare tickets.
The price of a ticket is specified via the constructor.
[Based on an exercise from Objects First With Java:
A Practical Introduction Using BlueJ.]
=cut
# my $price;# Price of a ticket from this machine.
# my $balance; # Amount of money entered by customer
# my $total;# Total amount of money collected by machine
# Create a machine that issues tickets of the given price.
# Price must be greater than zero (but no checks done).
sub new {
my $class = shift;
# In the BlueJ environment instances are automatically
# named behind the scenes (so far)...
my $instance = tm . int(rand(25));
my $self = { Name = $instance, Price = shift };
bless $self, $class;
}
sub getPrice {
my $self = shift;
return $self-{Price};
}
# more methods to come...
1;
__END__
In the Java version, the three variables are declared in the class first:
private int price;
private int balance;
private int total;
So in Perl I tried declaring these in the package using my, but they seemed
to remain class variables, so if I would do something like:
for (@ticket_machines) {
print A ticket costs , $_-getPrice(), cents.\n;
}
I would then get (for two machines):
A ticket costs 100 cents.
A ticket costs 100 cents.
Then I tried this with Perl...
In the new constructor:
my $class = shift;
my $price = shift;
my $self = $instance;
bless \$self, $class, $price;
...I was told too many arguments to bless. The Perl Objects book says the
easiest way to use more data with an instance is with a blessed hash
reference, and that did work fine (and maybe that's the best way).
But I'm wondering if there is another way (like the Java private variable)
to say all class variables declared here are unique to each instance?
It occurs to me that perhaps the difference is that in Perl you can call
methods on a class (i.e. the an unnamed horse from the Perl Objects book)
but not in Java (other than the contructor method)?
(If anyone is interested in BlueJ - www.bluej.org)
-K
--
Kevin Pfeiffer
International University Bremen
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RE: Split based on length
NYIMI Jose (BMB) wrote:
...
I was thinking about unpack function but how to make it dynamic ?
I mean writing :
my @items = unpack('A2 A2', $str);
Will work for $str='abdc';
Not for $str='abcdef';
How about something like:
my $s = 'abcdefghij';
my @x;
([EMAIL PROTECTED],$s) = unpack('a2 a*', $s) while length $s;
print @x\n;
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RE: Split based on length
Stephen Hardisty wrote:
for(split(/(..)/, $string)) { print *$_ if $_; }
Gorgeous :o)
or,
@parts = grep length, split /(..)/, $string;
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Net::SSH::Perl
Hi All, I remember i read somewhere about some limitations of Net::SSH::Perl on windows systems particularly something about 5.8 but can't find the link now. Can anybody point me to it without much effort.?? Thanx, -Sharad -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: instance variables?
But I'm wondering if there is another way
(like the Java private variable) to say
all class variables declared here are unique
to each instance?
It sounds like you are trying to link how OO-Perl works with OO-Java... and
that is only going to make your head spin. What you really need to do is
understand what bless really does, and that OO-Perl isn't really OO in the
usual sense (but it works like it is).
In Perl an object is really just a scalar variable that has been blessed.
Blessing adds an attribute to the scalar variable which is supposed to
represent the type of scalar. The only requirement is that the bless
scalar must be a reference.
my $x = foo;
my $y = bless \$x, bar;
print $y;
# PRINTS: bar=SCALAR(0xa01ed1c)
Here $y is a reference to a scalar (hence the SCALAR(0xa01ed1c)), and it
has been tagged as type bar.
That is all bless does.
Now the next part is the magic that Perl does...
$x-do_stuff;
Here $x does what looks like a method call. Perl will look at the type of
$x, which is foo, then try to execute do_stuff() in the foo package.
The first argument of this call will always be $x, like this:
foo:do_stuff($x);
This call does exactly the same thing as above.
Now when you talk about instance variables, realize that there is no true
object instance in Perl. It is just a reference tagged with a type... the
rest is all smoke and mirrors.
So to emmulate instance variables you can use a hash reference instead of a
scalar reference, like this:
my %x = (field1 = 'val1', field2 = 'val2');
my $y = bless \%x, bar;
Now $y is just a hash reference, so this stuff still works:
print $y-{field1};
print $y-{field2};
...And $y is also blessed, meaning you can emulate calling methods like I
did earlier.
Now you can still emulate private variables, but again, it's more smoke and
mirrors. Without getting into the details (look at 'tie' for more info) you
can just use the Tie::SecureHash module. It emulated public, protected, and
private variables.
http://search.cpan.org/author/DCONWAY/Tie-SecureHash-1.03/SecureHash.pm
I hope that helps a little.
Rob
-Original Message-
From: Kevin Pfeiffer [mailto:[EMAIL PROTECTED]
Sent: Thursday, September 18, 2003 1:32 PM
To: [EMAIL PROTECTED]
Subject: instance variables?
Hi all,
I stumbled across something called BlueJ which provides a user-friendly
graphical environment in which to learn OO-programming, Java-style. I think
this is a great parallel universe to go along with the Perl Objects book.
I started re-writing one of the first exercises as a Perl package:
[question follows below]
package TicketMachine;
# etc.
=head1 DESCRIPTION
TicketMachine models a naive ticket machine that issues
flat-fare tickets.
The price of a ticket is specified via the constructor.
[Based on an exercise from Objects First With Java:
A Practical Introduction Using BlueJ.]
=cut
# my $price;# Price of a ticket from this machine.
# my $balance; # Amount of money entered by customer
# my $total;# Total amount of money collected by machine
# Create a machine that issues tickets of the given price.
# Price must be greater than zero (but no checks done).
sub new {
my $class = shift;
# In the BlueJ environment instances are automatically
# named behind the scenes (so far)...
my $instance = tm . int(rand(25));
my $self = { Name = $instance, Price = shift };
bless $self, $class;
}
sub getPrice {
my $self = shift;
return $self-{Price};
}
# more methods to come...
1;
__END__
In the Java version, the three variables are declared in the class first:
private int price;
private int balance;
private int total;
So in Perl I tried declaring these in the package using my, but they seemed
to remain class variables, so if I would do something like:
for (@ticket_machines) {
print A ticket costs , $_-getPrice(), cents.\n;
}
I would then get (for two machines):
A ticket costs 100 cents.
A ticket costs 100 cents.
Then I tried this with Perl...
In the new constructor:
my $class = shift;
my $price = shift;
my $self = $instance;
bless \$self, $class, $price;
...I was told too many arguments to bless. The Perl Objects book says the
easiest way to use more data with an instance is with a blessed hash
reference, and that did work fine (and maybe that's the best way).
But I'm wondering if there is another way (like the Java private variable)
to say all class variables declared here are unique to each instance?
It occurs to me that perhaps the difference is that in Perl you can call
methods on a class (i.e. the an unnamed horse from the Perl Objects book)
but not in Java (other than the contructor method)?
(If anyone is interested in BlueJ - www.bluej.org)
-K
--
Kevin Pfeiffer
International University Bremen
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For additional commands,
RE: Problems with CPAN
John Birkhead wrote: Hi, I'm a perl newbie and I'm having problems getting CPAN connecting and downloading on SuSE 8.2. I start with 'perl -MCPAN -e shell' but the urlist is undefined. The default of 'ftp.perl.org' doesn't work. If I 'o conf urlist push ftp://cpan.nas.nasa.gov/pub/perl/CPAN' (or other mirror sites I've tried) when I download this url appears to be ignored and the downloads are attempted from the default. push will add to the end of the urllist. You can use unshift to add to the beginning. It also appears that when I exit and restart CPAN it has forgotten the url I added. use o conf commit to save changes -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: instance variables?
In article [EMAIL PROTECTED], Rob Hanson wrote: But I'm wondering if there is another way (like the Java private variable) to say all class variables declared here are unique to each instance? It sounds like you are trying to link how OO-Perl works with OO-Java... and that is only going to make your head spin. What you really need to do is understand what bless really does, and that OO-Perl isn't really OO in the usual sense (but it works like it is). [...] Now when you talk about instance variables, realize that there is no true object instance in Perl. It is just a reference tagged with a type... the rest is all smoke and mirrors. So to emulate instance variables you can use a hash reference instead of a scalar reference, like this: And this actually works quite fine I think... I hope that helps a little. Rob Thanks, that helped a lot! (Thank you also to others who responded.) Meanwhile my naive ticketMachine is chugging along. And I like doing the Perl version of something else; it's good practice for me (though I'm getting tired of typing my $self = shift;). ;-) -K -- Kevin Pfeiffer International University Bremen -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: instance variables?
Not quite right Rob :)
Rob Hanson wrote:
But I'm wondering if there is another way
(like the Java private variable) to say
all class variables declared here are unique
to each instance?
It sounds like you are trying to link how OO-Perl works with OO-Java... and
that is only going to make your head spin. What you really need to do is
understand what bless really does, and that OO-Perl isn't really OO in the
usual sense (but it works like it is).
In Perl an object is really just a scalar variable that has been blessed.
Blessing adds an attribute to the scalar variable which is supposed to
represent the type of scalar. The only requirement is that the bless
scalar must be a reference.
my $x = foo;
my $y = bless \$x, bar;
print $y;
# PRINTS: bar=SCALAR(0xa01ed1c)
Here $y is a reference to a scalar (hence the SCALAR(0xa01ed1c)), and it
has been tagged as type bar.
That is all bless does.
Now the next part is the magic that Perl does...
$x-do_stuff;
Here $x does what looks like a method call. Perl will look at the type of
$x, which is foo, then try to execute do_stuff() in the foo package.
The type of $x is 'bar' - you just said so above. Its value is
'foo', but usually you will want a lot more than just a single
scalar value in your object, so they are more usually hashes
as you say below.
The first argument of this call will always be $x, like this:
foo:do_stuff($x);
THis should be
bar::do_stuff($x)
This call does exactly the same thing as above.
Now when you talk about instance variables, realize that there is no true
object instance in Perl. It is just a reference tagged with a type... the
rest is all smoke and mirrors.
So to emmulate instance variables you can use a hash reference instead of a
scalar reference, like this:
my %x = (field1 = 'val1', field2 = 'val2');
my $y = bless \%x, bar;
Now $y is just a hash reference, so this stuff still works:
print $y-{field1};
print $y-{field2};
...And $y is also blessed, meaning you can emulate calling methods like I
did earlier.
Now you can still emulate private variables, but again, it's more smoke and
mirrors. Without getting into the details (look at 'tie' for more info) you
can just use the Tie::SecureHash module. It emulated public, protected, and
private variables.
http://search.cpan.org/author/DCONWAY/Tie-SecureHash-1.03/SecureHash.pm
It would be a Good Idea to get simple objects working before considering
private variables.
Cheers,
Rob
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RE: Split based on length
On Sep 18, Bob Showalter said:
Stephen Hardisty wrote:
for(split(/(..)/, $string)) { print *$_ if $_; }
Gorgeous :o)
@parts = grep length, split /(..)/, $string;
WHY are we using split() for this? Why are we using a method that returns
a list twice the size that we want, that we then have to filter through?
@parts = $string =~ /.{1,$len}/sg;
and you're done.
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RPI Acacia brother #734 http://www.perlmonks.org/ http://www.cpan.org/
stu what does y/// stand for? tenderpuss why, yansliterate of course.
[ I'm looking for programming work. If you like my work, let me know. ]
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Single and Double quotes in SQL
Hi! I need to save some HTML text in a DataBase (MySql, using DBI). However some HTML text will have single and double quotes, so.. how can I save them?, for example: align=centerIt's so funny/align Thanks! Pablo -- Pablo Fischer Sandoval (pablo -arroba- pablo.com.mx) http://www.pablo.com.mx http://www.debianmexico.org GPG FingerTip: 3D49 4CB8 8951 F2CA 8131 AF7C D1B9 1FB9 6B11 810C Firma URL: http://www.pablo.com.mx/firmagpg.txt -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Single and Double quotes in SQL
On Sat, 20 Sep 2003 21:34:58 +, Pablo Fischer wrote: I need to save some HTML text in a DataBase (MySql, using DBI). However some HTML text will have single and double quotes, so.. how can I save them?, for example: align=centerIt's so funny/align $html_text =~ s/'/''/g; $html_text =~ s///g; Use the help of regular expressions to double the number of each quote and mysql won't have any problems. thanks /oliver/ -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
perl modules in java
Hi All, Is it possible to use module perl modules (let say DBD::Xbase) in java? i'm sorry posting this java question to this perl forum, because no body (able to) answer this question in java forum.
