What is best way to create converter from function?

I want to apply func object as converter like this:

Func<int, double> f = x => x / 2.5;
Converter<int, double> convert = f;
List<double> applied_list = new List<int>(){1, 2, 3}.ConvertAll(convert);

Compiler gives me such message:

Error CS0029 Cannot implicitly convert type 'System.Func' to 'System.Converter'

What is best way to use function as converter?

Jon Skeet
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There are three options here. In my preferred order, they are:

  • Start using LINQ instead of ConvertAll:

    List<double> appliedList = new List { 1, 2, 3 }.Select(f).ToList();

  • Create a converter to start with:

    Converter<int, double> converter = x => x / 2.5;
List<double> appliedList = new List { 1, 2, 3 }.ConvertAll(converter);

  • If you really, really must, create a converter from the function using a delegate creation expression:

    Func<int, double> f = x => x / 2.5;
Converter<int, double> converter = new Converter<int, double>(f);
List<double> appliedList = new List { 1, 2, 3 }.ConvertAll(converter);

The last option creates a delegate that just wraps the original one.

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