godot-docs/tutorials/scripting/c_sharp/diagnostics/GD0402.rst

GD0402: The class must not be generic
=====================================

====================================  ======================================
                                      Value
====================================  ======================================
**Rule ID**                           GD0402
**Category**                          Usage
**Fix is breaking or non-breaking**   Breaking
**Enabled by default**                Yes
====================================  ======================================

Cause
-----

A generic type is annotated with the ``[GlobalClass]`` attribute.

Rule description
----------------

The Godot editor assumes every :ref:`global class <doc_c_sharp_global_classes>`
is instantiable, but generic types can't be instantiated because the type
parameters are unbound.

.. code-block:: csharp

    // This type is a valid global class because it's not generic.
    [GlobalClass]
    class SomeType : Node { }

    // This type is not a valid global class because it's generic.
    [GlobalClass]
    class SomeGenericType<T> { }

How to fix violations
---------------------

To fix a violation of this rule, change the type to remove the generic type parameters
or remove the ``[GlobalClass]`` attribute.

When to suppress warnings
-------------------------

Do not suppress a warning from this rule. Adding the ``[GlobalClass]`` to a
generic type is an easy mistake to make and this warning helps users realize
that it may result in unexpected errors.