package DX::Step::Backtrack;
use DX::DependencyMap;
-use DX::Utils qw(format_deps);
+use DX::Utils qw(format_deps compact_deps);
use DX::Class;
with 'DX::Role::Step';
my $rspace = $self->resolution_space;
trace backtrack => [ statement => [
[ symbol => 'backtrack' ],
- [ statement => [
- [ symbol => 'because' ],
- format_deps($rspace->geometry_depends_on)
- ] ]
+ [ 'enter_block' ]
+ ] ];
+ trace backtrack => [ word_and_body => [
+ 'failure_dependencies',
+ format_deps($rspace->geometry_depends_on)
] ];
my $dmap = DX::DependencyMap->new_empty
->with_dependencies_for(
backtrack => $rspace->geometry_depends_on
);
-
- foreach my $adj (@{$ss->decisions_taken}) {
+ DECISION: foreach my $adj (@{$ss->decisions_taken}) {
my ($rspace_was, $ss_was) = @$adj;
- $dmap = $dmap->with_dependencies_for(
- backtrack => $rspace_was->geometry_depends_on
- );
- next unless @{$rspace_was->remaining_resolution_space->members};
- trace rspace => [ statement => [
- [ symbol => 'remaining' ],
- @{$rspace_was->remaining_resolution_space->for_deparse->[1]}
+ trace backtrack => [ statement => [
+ [ symbol => 'decision' ],
+ [ pairs => [
+ [ for => $rspace_was->proposition, ],
+ [ aperture => [ block => [
+ map [ statement => [
+ [ symbol => (split '::', ${$_->[0]})[-1] ],
+ [ value_path => [ @{$_}[1..$#$_] ] ],
+ ] ], @{$rspace_was->aperture}
+ ] ] ]
+ ] ]
] ];
- return $ss_was->but(
- next_step => $rspace_was->remaining_resolution_space->next_step
- );
+ foreach my $event (@{$rspace_was->aperture}) {
+ if ($dmap->dependents_of($event)) {
+ my $remain = $rspace_was->remaining_resolution_space;
+ if (@{$remain->members}) {
+ trace backtrack => [ statement => [
+ [ symbol => 'found_alternative' ]
+ ] ];
+ trace backtrack => [ 'leave_block' ];
+ return $ss_was->but(
+ next_step => $remain->with_geometry_dependencies(
+ $dmap->dependencies_for('backtrack')
+ )->next_step
+ );
+ }
+ $dmap = $dmap->with_dependencies_for(
+ backtrack => $rspace_was->geometry_depends_on
+ );
+ trace backtrack => [ word_and_body => [
+ 'failure_dependencies',
+ format_deps(compact_deps($dmap->dependencies_for('backtrack')))
+ ] ];
+ next DECISION;
+ }
+ }
+ trace backtrack => [ statement => [ [ symbol => 'non_relevant' ] ] ];
}
- return $ss->but(next_step => $ss->on_exhaustion_step);
+ trace backtrack => [ statement => [ [ symbol => 'exhaustion' ] ] ];
+ trace backtrack => [ 'leave_block' ];
+ return $ss->but(
+ next_step
+ => $ss->on_exhaustion_step->but(
+ exhaustion_depends_on => $dmap->dependencies_for('backtrack')
+ )
+ );
}
1;