not and action infrastructure

[scpubgit/DKit.git] / lib / DX / RuleSet.pm

diff --git a/lib/DX/RuleSet.pm b/lib/DX/RuleSet.pm
index 13b6696..8840fb0 100644 (file)
--- a/lib/DX/RuleSet.pm
+++ b/lib/DX/RuleSet.pm
@@ -6,7 +6,11 @@ use DX::Op::MemberOf;
 use DX::Op::ApplyConstraint;
 use DX::Op::Return;
 use DX::Op::Cut;
+use DX::Op::Backtrack;
 use DX::Op::Observe;
+use DX::Op::Not;
+use DX::Op::ProposeAction;
+use DX::Op::Materialize;
 use List::Util qw(reduce);
 
 has rules => (is => 'ro', default => sub { {} });
@@ -20,15 +24,20 @@ sub add_rule {
 
 sub _make_rule {
   my ($self, $vars, @body) = @_;
-  my $head = reduce { $b->but(next => $a) }
-               DX::Op::Return->new,
-               reverse map $self->expand(@$_), @body;
+  my $head = $self->_expand_and_link(DX::Op::Return->new, @body);
   [ $vars, $head ];
 }
 
+sub _expand_and_link {
+  my ($self, $last, @body) = @_;
+  return reduce { $b->but(next => $a) }
+           $last,
+           reverse map $self->expand(@$_), @body;
+}
+
 sub expand {
   my ($self, $type, @rest) = @_;
-  if ($self->can(my $expand_meth = "_expand_${type}")) {
+  if ($self->can(my $expand_meth = "_expand_op_${type}")) {
     return $self->$expand_meth(@rest);
   }
   return $self->_expand_call($type, @rest);
@@ -39,9 +48,19 @@ sub _expand_call {
   DX::Op::CallRule->new(rule_name => $name, rule_args => \@args);
 }
 
-sub _expand_cut { return DX::Op::Cut->new }
+sub _expand_op_cut { return DX::Op::Cut->new }
 
-sub _expand_member_of {
+sub _expand_op_fail { return DX::Op::Backtrack->new }
+
+sub _expand_op_not {
+  my ($self, @contents) = @_;
+  my $cut = DX::Op::Cut->new(next => DX::Op::Backtrack->new);
+  DX::Op::Not->new(
+    body => $self->_expand_and_link($cut, @contents)
+  );
+}
+
+sub _expand_op_member_of {
   my ($self, $member_var, $coll_var) = @_;
   DX::Op::MemberOf->new(
     member_var => $member_var,
@@ -49,7 +68,7 @@ sub _expand_member_of {
   );
 }
 
-sub _expand_constrain {
+sub _expand_op_constrain {
   my ($self, $vars, $constraint) = @_;
   DX::Op::ApplyConstraint->new(
     vars => $vars,
@@ -57,7 +76,7 @@ sub _expand_constrain {
   );
 }
 
-sub _expand_observe {
+sub _expand_op_observe {
   my ($self, $vars, $builder) = @_;
   DX::Op::Observe->new(
     vars => $vars,
@@ -65,4 +84,17 @@ sub _expand_observe {
   );
 }
 
+sub _expand_op_act {
+  my ($self, $vars, $builder) = @_;
+  DX::Op::ProposeAction->new(
+    vars => $vars,
+    builder => $builder,
+  );
+}
+
+sub _expand_op_materialize {
+  my ($self, $var_name) = @_;
+  DX::Op::Materialize->new(var_name => $var_name);
+}
+
 1;