API needs to be able to report failure to detect, errors

[BartMassey]

Right now if something goes wrong — can't detect mode, error happens during detection attempt — detect() returns Mode::Light. Would be a lot better to provide some version of this that could return a Result.

[edfloreshz]

I believe this is by design, when a failure occurs Mode::Light is taken as the fallback mode.

Adding a Result would over-complicate things in my opinion, as an alternative I would suggest adding an Error variant to the Mode enum.

[BartMassey]

An Error "mode" means that every match against mode will need to handle this case. A Result can be checked for, leaving an actual mode to work with.

If the endpoint uses Result<Mode, Error> one can get the old behavior by

detect().unwrap_or(Mode::Light)

if desired.

[edfloreshz]

@frewsxcv What do you think? I think I brought this up at some point.

[frewsxcv]

Having it return a Result seems reasonable to me

[Rudxain]

Error variant

Isn't Default supposed to be for that?

[BartMassey]

Error variant

Isn't Default supposed to be for that?

I don't understand. Can you give an example of how Default might be useful here?

[Rudxain]

rust-dark-light/src/lib.rs

Lines 38 to 39 in 77ae434

	/// Unspecified
	Default,

That variant can be returned when the color-scheme is unknown for any reason.

But if we want to give more info to the API users, then wrapping Mode in a Result or Option is appropriate, as there's a difference between "something went very wrong whilst trying to fetch theme" and "no error happened, but theme is unknown for some reason"