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#!perl ## no critic (TidyCode)
use strict;
use warnings;
our $VERSION = 0;
use Object::Lazy;
my $object = Object::Lazy->new({
# A lazy Data::Dumper object as example
# will show you use or require late too.
build => sub {
require Data::Dumper;
return Data::Dumper->new(['data'], ['my_dump']);
},
# tell me when
logger => sub {
my $at_stack = shift;
() = print "Data::Dumper $at_stack";
},
});
sub do_something_with {
my ($object, $condition) = @_; ## no critic (ReusedNames)
if ($condition) {
# the Data::Dumper object will be created
() = print $object->Dump;
}
else {
# the Data::Dumper object is not created
}
() = print
"condition = $condition\n",
"object = $object\n";
return;
}
# do nothing
do_something_with($object, 0);
# build the real object and call method Dump
do_something_with($object, 1);
# $Id$
__END__
output:
condition = 0
object = Object::Lazy=HASH(...)
Data::Dumper object built at ../lib/Object/Lazy.pm line 35.
Object::Lazy::try {...} () called at D:/Perl/site/lib/Try/Tiny.pm line 81
eval {...} called at D:/Perl/site/lib/Try/Tiny.pm line 72
Try::Tiny::try(CODE(...), Try::Tiny::Catch=REF(...)) called at ../lib/Object/Lazy.pm line 39
Object::Lazy::BUILD_OBJECT(Data::Dumper=HASH(...), REF(...)) called at ../lib/Object/Lazy.pm line 53
Object::Lazy::AUTOLOAD(Data::Dumper=HASH(...)) called at 02_extended_constructor.pl line 29
main::do_something_with(Data::Dumper=HASH(...), 1) called at 02_extended_constructor.pl line 45
$my_dump = 'data';
condition = 1
object = Data::Dumper=HASH(...)
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