CA1005: Avoid excessive parameters on generic types
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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).
How to Fix Violations
To fix a violation of this rule, change the design to use no more than two type parameters.
When to Suppress Warnings
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.