File Coverage

blib/lib/Tie/Scalar/Decay.pm

Criterion	Covered	Total	%
statement	32	36	88.8
branch	6	8	75.0
condition	2	2	100.0
subroutine	7	8	87.5
pod			n/a
total	47	54	87.0

package Tie::Scalar::Decay;

use strict;

use Time::HiRes qw(time);    # if Time::HiRes isn't available for your
                             # system, then you can comment this out and
                             # it'll still work mostly.  However, test
                             # five will fail for obvious reasons

my $VERSION='1.1.1';

sub TIESCALAR {
	my $class = shift;
	my $self = {
		VALUE    => undef,
		PERIOD   => 5,
		FUNCTION => \&_defaultdecayfunction,
		@_
	};
	$self->{CREATION_TIME}=time;

	die("Tie::Scalar::Decay - invalid PERIOD.\n")
		unless($self->{PERIOD} =~ /^([0-9.]+)([smhd]?)$/);

	return bless $self, $class;
}

sub FETCH {
	my $self = shift;
	my $value=$self->{VALUE};

	return $value if(time < $self->{CREATION_TIME} + $self->_get_period());

	foreach(1..$self->_get_periods()) {
		if(ref($self->{FUNCTION}) eq 'CODE') {
			$value=&{$self->{FUNCTION}}($value);
		} else {
			eval($self->{FUNCTION});
		}
	}
	return $value;
}

sub STORE {
	my $self = shift;
	$self->{VALUE} = shift;
	$self->{CREATION_TIME}=time;
}

sub _defaultdecayfunction {
	my $value=$_[0];
	if($value=~/^-?[0-9\.]+$/) { return $value/2; }
	 else { return $value; }
}

sub _get_periods {
	my $self=shift;
	my $elapsedtime=time-$self->{CREATION_TIME};

	return int($elapsedtime/$self->_get_period());
}

sub _get_period {
	my $self=shift;
	my $period=$self->{PERIOD};
	my %mult = (
		's'=>1,
		'm'=>60,
		'h'=>3600,       # 60*60
		'd'=>86400,      # 60*60*24
	);
	$period=~s/^([0-9\.]+)([smhd]?)$/$1 * (($mult{$2})||1)/e;
	return $period;
}

1;
__END__