1 package DX::Step::Backtrack;
4 use DX::Utils qw(format_deps compact_deps);
9 has resolution_space => (is => 'ro', isa => ResolutionSpace, required => 1);
13 my $rspace = $self->resolution_space;
14 trace backtrack => [ statement => [
15 [ symbol => 'backtrack' ],
18 trace backtrack => [ word_and_body => [
19 'failure_dependencies',
20 format_deps($rspace->geometry_depends_on)
22 my $dmap = DX::DependencyMap->new_empty
23 ->with_dependencies_for(
24 backtrack => $rspace->geometry_depends_on
26 DECISION: foreach my $adj (@{$ss->decisions_taken}) {
27 my ($rspace_was, $ss_was) = @$adj;
28 trace backtrack => [ statement => [
29 [ symbol => 'decision' ],
31 [ for => $rspace_was->proposition, ],
32 [ aperture => [ block => [
34 [ symbol => (split '::', ${$_->[0]})[-1] ],
35 [ value_path => [ @{$_}[1..$#$_] ] ],
36 ] ], @{$rspace_was->aperture}
40 foreach my $event (@{$rspace_was->aperture}) {
41 if ($dmap->dependents_of($event)) {
42 my $remain = $rspace_was->remaining_resolution_space;
43 if (@{$remain->members}) {
44 trace backtrack => [ statement => [
45 [ symbol => 'found_alternative' ]
47 trace backtrack => [ 'leave_block' ];
49 next_step => $remain->with_geometry_dependencies(
50 $dmap->dependencies_for('backtrack')
54 $dmap = $dmap->with_dependencies_for(
55 backtrack => $rspace_was->geometry_depends_on
57 trace backtrack => [ word_and_body => [
58 'failure_dependencies',
59 format_deps(compact_deps($dmap->dependencies_for('backtrack')))
64 trace backtrack => [ statement => [ [ symbol => 'non_relevant' ] ] ];
66 trace backtrack => [ statement => [ [ symbol => 'exhaustion' ] ] ];
67 trace backtrack => [ 'leave_block' ];
70 => $ss->on_exhaustion_step->but(
71 exhaustion_depends_on => $dmap->dependencies_for('backtrack')