Added valueRestrictions to null and void Type

Author: TimoLehnertz

src/type/NeverType.php

@@ -2,7 +2,6 @@
 declare(strict_types = 1);
 namespace TimoLehnertz\formula\type;
 
-use TimoLehnertz\formula\nodes\NodeInterfaceType;
 use TimoLehnertz\formula\operator\ImplementableOperator;
 
 /**
@@ -26,10 +25,6 @@ public function getIdentifier(bool $isNested = false): string {
     return 'never';
   }
 
-  // public function getImplementedOperators(): array {
-  //   return [];
-  // }
-
   protected function getTypeOperatorResultType(ImplementableOperator $operator, ?Type $otherType): ?Type {
     return null;
   }

src/type/NullType.php

@@ -4,7 +4,6 @@
 
 namespace TimoLehnertz\formula\type;
 
-use TimoLehnertz\formula\nodes\NodeInterfaceType;
 use TimoLehnertz\formula\operator\ImplementableOperator;
 
 /**
@@ -13,7 +12,7 @@
 class NullType extends Type {
 
   public function __construct() {
-    parent::__construct();
+    parent::__construct([new NullValue()]);
   }
 
   protected function typeAssignableBy(Type $type): bool {
@@ -28,10 +27,6 @@ public function getIdentifier(bool $isNested = false): string {
     return 'null';
   }
 
-  // public function getImplementedOperators(): array {
-  //   return [];
-  // }
-
   protected function getTypeCompatibleOperands(ImplementableOperator $operator): array {
     return [];
   }

src/type/VoidType.php

@@ -10,7 +10,7 @@
 class VoidType extends Type {
 
   public function __construct() {
-    parent::__construct();
+    parent::__construct([new VoidValue()]);
   }
 
   public function getIdentifier(bool $nested = false): string {
@@ -25,10 +25,6 @@ public function equals(Type $type): bool {
     return $type instanceof VoidType;
   }
 
-  // public function getImplementedOperators(): array {
-  //   return [];
-  // }
-
   protected function getTypeCompatibleOperands(ImplementableOperator $operator): array {
     return [];
   }