I'm trying to roll out a strategy pattern with entity framework and the repository pattern using a simple example such as User and Post in which a user has many posts.

From this answer here, I have the following domain:

public interface IUser {
  public Guid UserId { get; set; }
  public string UserName { get; set; }
  public IEnumerable<Post> Posts { get; set; }
}

Add interfaces to support the roles in which you will use the user.

public interface IAddPostsToUser : IUser {
  public void AddPost(Post post);
}

Now my repository looks like this:

public interface IUserRepository {
  User Get<TRole>(Guid userId) where TRole : IUser;
}

Strategy (Where I'm stuck). What do I do with this code? Can I have an example of how to implement this, where do I put this?

public interface IFetchingStrategy<TRole> {
  TRole Fetch(Guid id, IRepository<TRole> role)
}

My basic problem was what was asked in this question. I'd like to be able to get Users without posts and users with posts using the strategy pattern.