Commit | Line | Data |
60cda014 |
1 | package DX::State; |
2 | |
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3 | use Return::MultiLevel qw(with_return); |
4 | use DX::Op::FromCode; |
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5 | use Scalar::Util qw(blessed); |
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6 | use Moo; |
7 | |
8 | has next_op => (is => 'ro', required => 1); |
9 | |
10 | has return_stack => (is => 'ro', required => 1); |
11 | |
12 | has by_id => (is => 'ro', required => 1); |
13 | |
14 | has scope => (is => 'ro', required => 1); |
15 | |
16 | has last_choice => (is => 'ro', required => 1); |
17 | |
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18 | has id_gen => (is => 'ro', default => sub { {} }); |
19 | |
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20 | sub scope_var { |
21 | my ($self, $name) = @_; |
22 | $self->by_id->{$self->scope->{$name}}; |
23 | } |
24 | |
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25 | sub allocate_var { |
26 | my ($self, $name, $var) = @_; |
27 | my $id = join('_', $name, ++($self->id_gen->{$name})); |
28 | DX::Var->new(id => $id, %$var); |
29 | } |
30 | |
31 | sub assign_vars { |
32 | my ($self, %vars) = @_; |
33 | my %by_id = %{$self->by_id}; |
34 | foreach my $name (keys %vars) { |
35 | warn "assign: ${name}"; |
36 | unless (blessed($vars{$name})) { |
37 | my $var = $vars{$name} = $self->allocate_var($name, $vars{$name}); |
38 | $by_id{$var->id} = $var; |
39 | } |
40 | } |
41 | $self->but( |
42 | by_id => \%by_id, |
43 | scope => { %{$self->scope}, map +($_ => $vars{$_}->id), keys %vars } |
44 | ); |
45 | } |
46 | |
b40d5c51 |
47 | sub bind_var_then { |
48 | my ($self, $var, $value, $then) = @_; |
49 | warn "Binding ".$var->id." to $value"; |
50 | my $bound = $var->with_value($value); |
51 | $self->but( |
52 | by_id => { %{$self->by_id}, $var->id => $bound }, |
53 | next_op => $then |
54 | ); |
55 | } |
56 | |
60cda014 |
57 | sub bind_stream_then { |
58 | my ($self, $var, $stream, $then) = @_; |
59 | warn "Binding ".$var->id." to $stream"; |
60 | my $bound = $var->with_stream($stream); |
03079510 |
61 | $self->but( |
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62 | by_id => { %{$self->by_id}, $var->id => $bound }, |
63 | next_op => $then |
64 | )->mark_choice($bound); |
65 | } |
66 | |
67 | sub mark_choice { |
68 | my ($self, $var) = @_; |
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69 | $self->but(last_choice => [ $self, $var ]); |
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70 | } |
71 | |
72 | sub backtrack { |
73 | my ($self) = @_; |
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74 | my ($state, $var) = ($self); |
75 | while (($state, $var) = @{$state->last_choice}) { |
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76 | $var->bound_value; $var->clear_bound_value; |
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77 | return $state->mark_choice($var) unless $var->bound_stream->is_exhausted; |
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78 | } |
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79 | $self->return_from_run(undef); |
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80 | } |
81 | |
82 | sub then { |
83 | my ($self, $then) = @_; |
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84 | $self->but(next_op => $then); |
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85 | } |
86 | |
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87 | sub return_from_run { |
88 | my (undef, $return) = @_; |
89 | (our $Nonlocal_Return)->($return); |
90 | } |
91 | |
94565614 |
92 | sub run { |
93 | my ($state) = @_; |
5622b4df |
94 | with_return { |
95 | my ($return) = @_; |
b40d5c51 |
96 | local our $Nonlocal_Return = $return; |
54817920 |
97 | while (my $op = $state->next_op) { |
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98 | #::Dwarn($op); |
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99 | $state = $op->run($state); |
100 | } |
101 | return $state; |
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102 | } |
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103 | } |
104 | |
105 | sub push_backtrack { |
106 | $_[0]->then(DX::Op::FromCode->new(code => sub { $_[1]->backtrack })); |
94565614 |
107 | } |
108 | |
03079510 |
109 | sub but { |
110 | my ($self, @but) = @_; |
111 | $self->new(%$self, @but); |
112 | } |
113 | |
b40d5c51 |
114 | sub pop_return_stack { |
115 | my ($self) = @_; |
116 | my @stack = @{$self->return_stack}; |
117 | my $top = pop @stack; |
118 | $self->but(return_stack => \@stack, next_op => $top); |
119 | } |
120 | |
121 | sub push_return_then { |
122 | my ($self, $return, $then) = @_; |
123 | $self->but( |
124 | return_stack => [ @{$self->return_stack}, $return ], |
125 | next_op => $then |
126 | ); |
127 | } |
128 | |
60cda014 |
129 | 1; |