Fix ambiguous syntax parsing

tests/IntegrationTest.php

@@ -164,6 +164,7 @@ class TwigTestExtension extends AbstractExtension
             new TwigFilter('magic_call_array', ['Twig\Tests\TwigTestExtension', 'magicStaticCall']),
             new TwigFilter('*_path', [$this, 'dynamic_path']),
             new TwigFilter('*_foo_*_bar', [$this, 'dynamic_foo']),
+            new TwigFilter('not', [$this, 'notFilter']),
         ];
     }
 
@@ -188,6 +189,11 @@ class TwigTestExtension extends AbstractExtension
         ];
     }
 
+    public function notFilter($value)
+    {
+        return 'not '.$value;
+    }
+
     public function §Filter($value)
     {
         return "§{$value}§";