diff --git a/lbplanner/classes/enums/CAPABILITY.php b/lbplanner/classes/enums/CAPABILITY.php
index 4822779..22e44a8 100644
--- a/lbplanner/classes/enums/CAPABILITY.php
+++ b/lbplanner/classes/enums/CAPABILITY.php
@@ -62,6 +62,6 @@ class CAPABILITY extends Enum {
      */
     public static function to_capability(string $str): int {
         $name = self::name_from($str);
-        return CAPABILITY_FLAG::{$name};
+        return constant('CAPABILITY_FLAG::'.$name);
     }
 }
diff --git a/lbplanner/classes/enums/CAPABILITY_FLAG.php b/lbplanner/classes/enums/CAPABILITY_FLAG.php
index a858461..5419ebf 100644
--- a/lbplanner/classes/enums/CAPABILITY_FLAG.php
+++ b/lbplanner/classes/enums/CAPABILITY_FLAG.php
@@ -62,6 +62,6 @@ class CAPABILITY_FLAG extends Enum {
      */
     public static function to_capability(int $num): string {
         $name = self::name_from($num);
-        return CAPABILITY::{$name};
+        return constant('CAPABILITY::'.$name);
     }
 }