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doc/component/Walking_the_AST.markdown

@@ -296,7 +296,7 @@ for minor tasks. For this reason a `NodeFinder` is provided, which can find AST
 satisfy a certain callback, or which are instanced of a certain node type. A couple of examples are
 shown in the following:
 
-```
+```php
 use PhpParser\{Node, NodeFinder};
 
 $nodeFinder = new NodeFinder;