Fix link match disregard of deeper assignments

das/pattern_matcher/pattern_matcher.py

@@ -457,7 +457,7 @@ def __repr__(self):
 
     def get_handle(self, db: DBInterface) -> str:
         if not self.handle:
-            target_handles = [target.get_handle(db) for target in self.targets]
+            target_handles = [target if type(target) is str else target.get_handle(db) for target in self.targets]
             if any(handle is None for handle in target_handles):
                 return None
             self.handle = db.get_link_handle(self.atom_type, target_handles)
@@ -499,6 +499,29 @@ def _typed_variable_matched(self, db: DBInterface, answer: PatternMatchingAnswer
                 first_typed_variable = False
         return all(target.matched(db, answer) for target in self.targets)
 
+    def _apply_assignment(self, assignment: OrderedAssignment, db: DBInterface) -> str:
+        targets = []
+        for t in self.targets:
+            if type(t) is Node:
+                targets.append(t.get_handle(db))
+            elif type(t) is Link:
+                targets.append(t._apply_assignment(assignment, db))
+            elif type(t) is Variable or type(t) is TypedVariable:
+                targets.append(assignment.mapping[t.name])
+        link = Link(self.atom_type, targets, self.ordered)
+        return link.get_handle(db)
+
+    def apply_assignment(self, assignment: OrderedAssignment, db: DBInterface) -> str:
+        targets = []
+        for t in self.targets:
+            if type(t) is Node:
+                targets.append(t.get_handle(db))
+            elif type(t) is Link:
+                targets.append(t._apply_assignment(assignment, db))
+            elif type(t) is Variable or type(t) is TypedVariable:
+                targets.append(assignment.mapping[t.name])
+        return Link(self.atom_type, targets, self.ordered)
+
     def matched(self, db: DBInterface, answer: PatternMatchingAnswer) -> bool:
         if DEBUG_LINK: print('link match', self)
         if any(isinstance(atom, LinkTemplate) for atom in self.targets):
@@ -535,7 +558,17 @@ def matched(self, db: DBInterface, answer: PatternMatchingAnswer) -> bool:
             return bool(answer.assignments)
         else:
             if DEBUG_LINK: print('matched()', f'leaving 2 self = {self}')
-            return db.link_exists(self.atom_type, target_handles) or bool(answer.assignments)
+            if db.link_exists(self.atom_type, target_handles):
+                return True
+            else:
+                new_assignments = set()
+                for assignment in answer.assignments:
+                    assert type(assignment) is OrderedAssignment
+                    link = self.apply_assignment(assignment, db)
+                    if db.link_exists(link.atom_type, link.targets):
+                        new_assignments.add(assignment)
+                answer.assignments = new_assignments
+                return bool(answer.assignments)
 
 class Variable(Atom):
     """