Timestamps on the events?

[waywardmonkeys]

In the browser, KeyEvent and CompositionEvent inherit from Event which has a timestamp. In doing some PointerEvent stuff, I have a timestamp available (since this is useful for doing predicted events from sequences of events).

Would there be interest in adding a timestamp: u64 to KeyEvent and CompositionEvent?

[madsmtm]

Hmm, if we're to have a time stamp, I'd somewhat prefer using std::time::Instant (or web_time::Instant in WASM). But that also kinda conflicts with #17.

[waywardmonkeys]

The problem with std::time::Instant is that you can't access or set the value if you're doing things like bridging events, so you can't use the value that the platform gives you to populate it, and if you're converting from another event structure into this one, you can't set it either to a value corresponding to the other.

[waywardmonkeys]

You could use core::time::Duration with a flexible interpretation of what the epoch is though.

[madsmtm]

Hmm, yeah. I guess std::time::SystemTime is more meant for transferring over the wire, but you don't actually want the strong guarantees that those provide.

[madsmtm]

Another thing to note is that there's many other fields on the inheritance chain of KeyboardEvent (Event.srcElement, Event.target, UIEvent.view), and it's immediately clear to me where we draw the line?

That of course still shouldn't be an argument against adding this if it's useful, just interesting to discuss.

[madsmtm]

I don't have a strong opinion here either way, will let @pyfisch decide.

[pyfisch]

I don't want to add timestamps (or other metadata) to the event type. Keyboard-types was designed with browser uses (in particular servo) in mind.

While in JS you have an event class with attributes such as timeStamp and target from which specific events classes inherit, Servo uses composition instead: There is an Event struct that contains shared attributes with one attribute containing an enum for all the different types: keyboard, mouse, message events, etc. Each variant in turn contains the attributes specific to that event type.

Let me know if that explanation was clear, you can also look up the event types in servo.

[waywardmonkeys]

Sounds good to me! Thanks!