switch adjustments to keep search state to preserve on_X_step values
[scpubgit/DX.git] / lib / DX / Step / Backtrack.pm
1 package DX::Step::Backtrack;
2
3 use DX::Class;
4
5 with 'DX::Role::Step';
6
7 sub apply_to {
8   my ($self, $ss) = @_;
9   my ($first_alt, @rest_alt) = @{$ss->adjustments_made};
10   return $ss->but(next_step => $ss->on_exhaustion_step) unless $first_alt;
11   return $first_alt->[1]->but(next_step => $first_alt->[0]->alternative_step);
12 }
13
14 1;