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 (undef, $self->alternative_step) unless $new_hyp;
+ return $ss->but(next_step => DX::Step::Backtrack->new) unless $new_hyp;
trace 'step.apply.new_hyp '.$self => $new_hyp;
- return ($ss->but(current_hypothesis => $new_hyp), $self->alternative_step);
+ 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 {