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[Solved] The generic type already contains a definition

Hello Guys, How are you all? Hope You all Are Fine. Today I try to define the following Pair<A, B> class in C#, I get a compiler error. The compiler error is error CS0102: The type ‘Pair’ already contains a definition for ‘A’ in C#. So Here I am Explain to you all the possible solutions here.

Without Wasting your time, Lets start This Article to Solve This Error.

How The generic type already contains a definition Error Occurs ?

Today I try to define the following Pair<A, B> class in C#, I get a compiler error. The compiler error is error CS0102: The type ‘Pair’ already contains a definition for ‘A’ in C#

error CS0102: The type 'Pair<A, B>' already contains a definition for 'A'
error CS0102: The type 'Pair<A, B>' already contains a definition for 'B'

How To Solve The generic type already contains a definition Error ?

Question: How To Solve The generic type already contains a definition Error ?
Answer: The name of a type parameter in the type_parameter_list of a class declaration shall differ from the names of all other type parameters in the same type_parameter_list and shall differ from the name of the class and the names of all members of the class.

Solution 1

As Per Theirs Document

The name of a type parameter in the type_parameter_list of a class declaration shall differ from the names of all other type parameters in the same type_parameter_list and shall differ from the name of the class and the names of all members of the class.

Meanwhile, you can’t get a type parameter the same name as another type parameter or a class member. Here, you have a type parameter called A and a property called A. In this example, the error message suddenly makes sense

class Broken<T>
{
    public string T { get; set; }
}

Summery

It’s all About this issue. Hope all solution helped you a lot. Comment below Your thoughts and your queries. Also, Comment below which solution worked for you?

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