File Coverage

blib/lib/GIS/Distance.pm

Criterion	Covered	Total	%
statement	23	24	95.8
branch	8	12	66.6
condition	2	5	40.0
subroutine	4	4	100.0
pod	0	1	0.0
total	37	46	80.4

package GIS::Distance;
use 5.008001;
use strictures 2;
our $VERSION = '0.19';

sub new {
    my ($class, $formula, @args) = @_;

    $formula ||= 'Haversine';

    my @modules;
    push @modules, "GIS::Distance::Fast::${formula}"
        unless $ENV{GIS_DISTANCE_PP} or $ENV{GEO_DISTANCE_PP};
    push @modules, "GIS::Distance::$formula";
    push @modules, $formula;

    foreach my $module (@modules) {
        next if !_try_load_module( $module );
        next if !$module->isa('GIS::Distance::Formula');

        return $module->new( @args );
    }

    die "Cannot find a GIS::Distance::Formula class for $formula";
};

my %tried_modules;

sub _try_load_module {
    my ($module) = @_;

    return $tried_modules{ $module }
        if defined $tried_modules{ $module };

    $tried_modules{ $module } = 1;
    my $ok = eval( "require $module; 1" );
    return 1 if $ok;

    $tried_modules{ $module } = 0;
    die $@ if $@ !~ m{^Can't locate};
    return 0;
}

1;
__END__