[scpubgit/DX.git] / lib / DX / Step / Backtrack.pm

package DX::Step::Backtrack;

use DX::Class;

with 'DX::Role::Step';

sub apply_to {
  my ($self, $ss) = @_;
  trace backtrack => [ statement => [ [ symbol => 'backtrack' ] ] ];
  foreach my $adj (@{$ss->adjustments_made}) {
    my ($step_was, $ss_was) = @$adj;
    if (my $alt = $step_was->alternative_step) {
      return $ss_was->but(next_step => $alt);
    }
  }
  return $ss->but(next_step => $ss->on_exhaustion_step);
}

1;
Commit	Line	Data
55131db4	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) = @_;
5b6cab1b	9	trace backtrack => [ statement => [ [ symbol => 'backtrack' ] ] ];
76329453	10	foreach my $adj (@{$ss->adjustments_made}) {
	11	my ($step_was, $ss_was) = @$adj;
	12	if (my $alt = $step_was->alternative_step) {
	13	return $ss_was->but(next_step => $alt);
	14	}
	15	}
	16	return $ss->but(next_step => $ss->on_exhaustion_step);
55131db4	17	}
	18
	19	1;