The Managed Extensibility Framework or MEF is a library for creating lightweight, extensible applications that introduced in the .NET framework 4.
In order the understand MEF, the document is helpful from MSDN. The link: https://msdn.microsoft.com/en-us/library/dd460648(v=vs.110).aspx
In this document, there is an calculator example. In this source code, the example is taken, enhanced and adapted to .NET Core. "Structure.txt" contains some explanation about the example in addition to necessary comment lines.
For this example, Visual Studio 2015 Community Edition is preffered as IDE.
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