has depends_on => (is => 'ro', isa => DependencyGroupList, required => 1);
+has resolves => (is => 'ro', isa => Proposition);
+
has alternative_step => (is => 'ro', isa => Step);
+sub but_first {
+ my ($self, @actions) = @_;
+ $self->but(actions => [ @actions, @{$self->actions} ]);
+}
+
sub but_with_dependencies_on {
my ($self, @deps) = @_;
$self->but(depends_on => [ @{$self->depends_on}, @deps ]);
}
-sub but_with_alternative_step {
- my ($self, $step) = @_;
- bless { %$self, alternative_step => $step }, ref($self);
-}
-
sub apply_to {
- my ($self, $old_hyp) = @_;
- return ($self->_apply_to_hyp($old_hyp), $self->alternative_step);
+ my ($self, $ss) = @_;
+ my $old_hyp = $ss->current_hypothesis;
+ trace 'step.apply.old_hyp '.$self => $old_hyp;
+ trace 'step.apply.actions '.$self => $self->actions;
+ my $new_hyp = $self->_apply_to_hyp($old_hyp);
+ return $ss->but(next_step => DX::Step::Backtrack->new) unless $new_hyp;
+ trace 'step.apply.new_hyp '.$self => $new_hyp;
+ my $ns = do {
+ if (my $prop = $ss->next_proposition($new_hyp)) {
+ DX::Step::ConsiderProposition->new(
+ proposition => $prop
+ )
+ } else {
+ $ss->on_solution_step
+ }
+ };
+ my $alt_step = $self->alternative_step;
+ return (
+ $ss->but(
+ current_hypothesis => $new_hyp,
+ next_step => $ns,
+ ($alt_step
+ ? (alternatives => [ [ $old_hyp, $alt_step ], @{$ss->alternatives} ])
+ : ()
+ ),
+ ),
+ );
}
sub _apply_to_hyp {
my ($self, $old_hyp) = @_;
return undef unless my $hyp = $old_hyp->with_actions(@{$self->actions});
- return $hyp->resolve_head_dependent_on($self->depends_on);
+ return $hyp->with_resolution($self->resolves, $self->depends_on);
}
1;