Convert DateTime instance to DateOnly or TimeOnly

Background and motivation

The Fluent Assertion syntax for DateTime objects (e. g. 12.April(1953).At(19, 53)) is phantastic. But IMHO it could be even better with two new extension methods .ToDateOnly() and .ToTimeOnly(). This would allow keeping a fluent syntax (instead of new DateOnly(1953, 4, 12)) and shorter (instead of DateOnly.FromDateTime(12.April(1953))) .

API Proposal

public static class FluentDateTimeExtensions
{
    public static DateOnly ToDateOnly(this DateTime date);

    public static TimeOnly ToTimeOnly(this DateTime date);
}

API Usage

var now = 12.April(1953);

var date = now.ToDateOnly();
var time = now.ToTimeOnly();

Alternative Designs

/

Risks

Since it’s only a new extension method to be added, a regression or breaking change should not happen.

[jnyrup]

Although I think I would prefer AsTimeOnly and AsDateOnly

As we’re converting another type and truncating, I vote for using the To prefix.

https://stackoverflow.com/questions/13867829/to-vs-as-vs-get-method-prefixes

[mu88]

For a time I could agree with your arguments: new(13, 37) is okayish to read, concise, and probably unambiguous.

But for a date writing new(1953, 4, 12) doesn’t feel good to me, as it could be both April 12 or December 4 if you’re not familiar with the API.