MudBlazor: 'CategoryTypes.Element': static types cannot be used as type arguments

Question

I'm trying to implement a MudTable with grouping with the MudBlazor component library. As per the documentation, you must define the group definition like so:

@code { 
    private TableGroupDefinition<Element> _groupDefinition = new()
    {
        GroupName = "Group",
        Indentation = false,
        Expandable = true,
        IsInitiallyExpanded = false,
        Selector = (e) => e.Group
    };
}

Which is used in the component like so:

<MudTable Items="@Elements"
          ...
          GroupBy="@_groupDefinition">

However I get the following errors:

On _groupDefinition: CS0718: CategoryTypes.Element: static types cannot be used as type arguments

On (e) CS0721: CategoryTypes.Element: static types cannot be used as parameters

I understand that static classes cannot be instantiated and therefore the errors make sense, but how did the developers get this to compile?

I am using .net 6, Blazor Webassembly, and MudBlazor v6.0.10.

Answer 1

As commented by Jesse Good, I got caught out by the example having a class of Element which also existed in the MudBlazor Library as a static class! I replaced that class with my own, i.e.:

        private TableGroupDefinition<Subcategory> _groupDefinition = new()
        {
            GroupName = "Category",
            Indentation = false,
            Expandable = true,
            IsInitiallyExpanded = false,
            Selector = (c) => c.CategoryId
        };