3 use Return::MultiLevel qw(with_return);
7 has next_op => (is => 'ro', required => 1);
9 has return_stack => (is => 'ro', required => 1);
11 has by_id => (is => 'ro', required => 1);
13 has scope => (is => 'ro', required => 1);
15 has last_choice => (is => 'ro', required => 1);
18 my ($self, $name) = @_;
19 $self->by_id->{$self->scope->{$name}};
23 my ($self, $var, $value, $then) = @_;
24 warn "Binding ".$var->id." to $value";
25 my $bound = $var->with_value($value);
27 by_id => { %{$self->by_id}, $var->id => $bound },
32 sub bind_stream_then {
33 my ($self, $var, $stream, $then) = @_;
34 warn "Binding ".$var->id." to $stream";
35 my $bound = $var->with_stream($stream);
37 by_id => { %{$self->by_id}, $var->id => $bound },
39 )->mark_choice($bound);
43 my ($self, $var) = @_;
44 $self->but(last_choice => [ $self, $var ]);
49 my ($state, $var) = ($self);
50 while (($state, $var) = @{$state->last_choice}) {
51 $var->bound_value; $var->clear_bound_value;
52 return $state->mark_choice($var) unless $var->bound_stream->is_exhausted;
54 $self->return_from_run(undef);
58 my ($self, $then) = @_;
59 $self->but(next_op => $then);
63 my (undef, $return) = @_;
64 (our $Nonlocal_Return)->($return);
71 local our $Nonlocal_Return = $return;
72 while (my $op = $state->next_op) {
73 $state = $op->run($state);
80 $_[0]->then(DX::Op::FromCode->new(code => sub { $_[1]->backtrack }));
84 my ($self, @but) = @_;
85 $self->new(%$self, @but);
88 sub pop_return_stack {
90 my @stack = @{$self->return_stack};
92 $self->but(return_stack => \@stack, next_op => $top);
95 sub push_return_then {
96 my ($self, $return, $then) = @_;
98 return_stack => [ @{$self->return_stack}, $return ],