6 use List::Util qw(reduce);
9 has rule_set => (is => 'lazy', handles => [ 'add_rule' ], builder => sub {
13 has facts => (is => 'ro', required => 1);
15 has observation_policy => (is => 'ro');
18 my ($self, $vars, @terms) = @_;
19 my $rule_set = $self->rule_set;
20 push @terms, map +[ materialize => $_ ], @$vars;
21 my $head = reduce { $b->but(next => $a) }
22 reverse map $rule_set->expand(@$_), @terms;
23 my $state = DX::State->new(
29 facts => $self->facts,
30 rule_set => $rule_set,
31 )->assign_vars(map +($_ => {}), @$vars);
32 return DX::ResultStream->new(
34 ($self->observation_policy
35 ? (observation_policy => $self->observation_policy)