I am trying to figure out the most efficient method of passing around a live
dbh when calling a subs.
I have embedded a dbh into an object: $obj-{dbh} and would like to pass to
it to other functions for reuse.
Should I call: foo( $obj-{dbh} );
or: foo( \$obj-{dbh} );
or something else?
Does the
call: foo( $obj-{dbh} );
First of all, the dbh is already a reference. There is
no point in creating another one.
Secondly, when you pass variables as arguments to a
perl function, it actually operates on the variable.
If you modify the variable, the variable is modified
in the callers context.
Message-
From: Alec Brecher [mailto:[EMAIL PROTECTED]
Sent: Monday, January 10, 2005 8:35 AM
To: Dbi-Users
Subject: passing dbh
I am trying to figure out the most efficient method of passing around a live
dbh when calling a subs.
I have embedded a dbh into an object: $obj-{dbh} and would like
On Mon, Jan 10, 2005 at 10:35:16AM -0500, Alec Brecher wrote:
I am trying to figure out the most efficient method of passing around a live
dbh when calling a subs.
Since Perl passes sub arguments by reference, it is already fairly
efficient. Plus, it is unlikely the overhead of passing a
the entire object:
bar( $obj ); not just the dbh.
Thank you again. -Alec
-Original Message-
From: David [mailto:[EMAIL PROTECTED]
Sent: Monday, January 10, 2005 11:10 AM
To: Dbi-Users
Subject: Re: passing dbh
On Mon, Jan 10, 2005 at 10:35:16AM -0500, Alec Brecher wrote:
I am trying
:
Subject:RE: passing dbh
Thanks to all who replied. My biggest concern was that copying the dbh
meant that a new connection would be created. And somehow had the
impression
that arguements were passed by value not reference.
The reason for embedding the dbh into the obj: $obj-{dbh
On Mon, Jan 10, 2005 at 12:28:44PM -0500, [EMAIL PROTECTED] wrote:
I hate confusion, so I went to the source: perldoc perlsub, and here is
what it had to say:
The Perl model for function call and return values is simple: all
functions are passed as parameters one single flat
list
This thread is getting a bit OT, but...
David [EMAIL PROTECTED] 01/10/05 12:36PM
On Mon, Jan 10, 2005 at 12:28:44PM -0500,
[EMAIL PROTECTED] wrote:
Passing arguments explicitly by reference is only useful is you want
to
pass an array or hash as a single entity.
HM I respectfully disagree :)
Damn I hate being publicly wrong, but you're right.
#!/usr/bin/perl -w
use strict;
my $a = 1;
foo($a);
print $a\n;
sub foo {
$_[0] = 2;
}
prints '2'. It's shifting them off that list that creates the copy I am
used to working with.
But it still remains true that passing $dbh is safe
