create an object where type is a variable

true_atlantis has asked for the wisdom of the Perl Monks concerning the following question:

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Re: create an object where type is a variable by ikegami (Patriarch) on Sep 11, 2007 at 15:26 UTC
Your code works as is. The parens are not needed, by the way.	[reply]
Re^2: create an object where type is a variable by merlyn (Sage) on Sep 11, 2007 at 15:37 UTC
"Works", presuming for any value of $x, the corresponding class understands an empty `new` call to mean "return a reasonable object of type $x". Have to say this since there's absolutely nothing special about calling `new`: it's just a method call. -- Randal L. Schwartz, Perl hacker	[reply] [d/l] [select]
Re^3: create an object where type is a variable by true_atlantis (Acolyte) on Sep 11, 2007 at 15:44 UTC
Ahh... my problem was that i was trying to do something like this: `use test::object; my $x='object'; my $y=test::$x->new();` [download] That didnt work, and i just realized it was because you have to concat the 'test::' and $x... just in case anyone is running into the same issue, it would look like this: `use test::object; my $x='object'; my $y=test::.$x->new();` [download] Thank you everyone.	[reply] [d/l] [select]
Re^4: create an object where type is a variable by merlyn (Sage) on Sep 11, 2007 at 16:03 UTC
Re^5: create an object where type is a variable by jdporter (Paladin) on Sep 11, 2007 at 16:16 UTC
Re: create an object where type is a variable by leocharre (Priest) on Sep 11, 2007 at 15:48 UTC
How weird, I didn't know.. `#!/usr/bin/perl -w use Test::Simple 'no_plan'; use strict; use warnings; use CGI::Session; my $x = 'CGI::Session'; my $z = 'new'; my $y = $x->$z; ok($y,'instanced'); print STDERR $y->header;` [download] output: loot@moonshine dev# perl /tmp/test.pl ok 1 - instanced Set-Cookie: CGISESSID=71079ce5211b3e460f8924c780ff9c0b; Date: Tue, 11 Sep 2007 15:48:01 GMT Content-Type: text/html; charset=ISO-8859-1 1..1	[reply] [d/l]
Re: create an object where type is a variable by naikonta (Curate) on Sep 11, 2007 at 15:57 UTC
Yes, no problem. You can also use a variable in the whole process. For example if you need to load a series of modules, `my %objects; for my $class (@available_classes) { eval qq(require $class); if ($@) { # you can make it die() here, if you want warn "Failed to load class '$class': $@"; next; } $objects{$class} = $class->new; }` [download] Because the way require works, you have to eval the `require $class` statement in double quotes so the `$class` becomes bareword. Or, you may have to pick a correct class by certain criteria. You can use UNIVERSAL::require in place of the eval statement and `$@` checking. `use UNIVERSAL::require; my $class = get_implementor_class(); #defined somewhere $class->use or die $@; my $object = $class->new;` [download] Open source softwares? Share and enjoy. Make profit from them if you can. Yet, share and enjoy!	[reply] [d/l] [select]