There should be a ConfigurationProvider

[MovGP0]

There should be a reference implementation of Microsoft.Extensions.Configuration.IConfigurationProvider that works with the FluentCommandLineParser class.

https://andrewlock.net/creating-a-custom-iconfigurationprovider-in-asp-net-core-to-parse-yaml/

[siywilliams]

Looks interesting but I've not come across IConfigurationProvider myself yet.

My concern is adding a dependency to Microsoft.Extensions.Configuration (FCLP currently has no external dependencies, something I've tried to maintain).

The correct way to go about this would be to create another extension project, for example something like FluentCommandLineParser.ConfigurationProvider which would provide the extensions to add this functionality without polluting the main project.

[astrohart]

@siywilliams that is the way to go. Separate extension project and in its own NuGet package. This way, I can add that to my project only if I want/need it.