I'd use tie() instead. This module will untie the variable and replace it with its value the first time the variable is fetched.
package Tie::Scalar::Lazy;
# usage:
# use Tie::Scalar::Lazy;
# lazy $value => \&expensive_function;
require Exporter;
@ISA = qw( Exporter );
@EXPORT = qw( lazy );
sub lazy {
tie $_[0], __PACKAGE__, \$_[0], $_[1];
}
sub TIESCALAR {
my ($class, $sref, $cref) = @_;
bless [ $sref, $cref ], $class;
}
sub FETCH {
my $self = shift;
my $value = $self->[1]->();
untie ${ $self->[0] };
${ $self->[0] } = $value;
}
1;
_____________________________________________________
Jeff[japhy]Pinyan:
Perl,
regex,
and perl
hacker, who'd like a (from-home) job
s++=END;++y(;-P)}y js++=;shajsj<++y(p-q)}?print:??;
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