Avoid excessive parameters on generic types
Avoid excessive parameters on generic types
Microsoft docsDescription
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).
Cause
An externally visible generic type has more than two type parameters.
By default, this rule only looks at externally visible types, but this is configurable.
How to fix violations
To fix a violation of this rule, change the design to use no more than two type parameters.
Example
#pragma warning disable CA1005
// The code that's violating the rule is on this line.
#pragma warning restore CA1005When to suppress
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.