CA1005: Avoid excessive parameters on generic types
For the latest documentation on Visual Studio 2017, see Visual Studio 2017 Documentation.
An externally visible generic type has more than two type parameters.
The more type parameters a generic type contains, the more difficult it is to know and remember what each type parameter represents. It is usually obvious with one type parameter, as in
List<T>, and in certain cases with two type parameters, as in
Dictionary<TKey, TValue>. If more than two type parameters exist, the difficulty becomes too great for most users (for example,
TooManyTypeParameters<T, K, V> in C# or
TooManyTypeParameters(Of T, K, V) in Visual Basic).
To fix a violation of this rule, change the design to use no more than two type parameters.
Do not suppress a warning from this rule unless the design absolutely requires more than two type parameters. Providing generics in a syntax that is easy to understand and use reduces the time that is required to learn and increases the adoption rate of new libraries.