Add missing class declaration

src/core/expression/qgsexpressionfunction.h

@@ -521,6 +521,29 @@ class QgsArrayForeachExpressionFunction : public QgsExpressionFunction
 
 };
 
+/**
+ * Handles the ``array_foreach(array, expression)`` expression function.
+ * It temporarily appends a new scope to the expression context.
+ *
+ * \ingroup core
+ * \note Not available in Python bindings
+ * \since QGIS 3.4
+ */
+class QgsArrayFilterExpressionFunction : public QgsExpressionFunction
+{
+  public:
+    QgsArrayFilterExpressionFunction();
+
+    bool isStatic( const QgsExpressionNodeFunction *node, QgsExpression *parent, const QgsExpressionContext *context ) const override;
+
+    QVariant run( QgsExpressionNode::NodeList *args, const QgsExpressionContext *context, QgsExpression *parent, const QgsExpressionNodeFunction *node ) override;
+
+    QVariant func( const QVariantList &values, const QgsExpressionContext *context, QgsExpression *parent, const QgsExpressionNodeFunction *node ) override;
+
+    bool prepare( const QgsExpressionNodeFunction *node, QgsExpression *parent, const QgsExpressionContext *context ) const override;
+
+};
+
 /**
  * Handles the ``with_variable(name, value, node)`` expression function.
  * It temporarily appends a new scope to the expression context for all nested