Packages that provide support for external events such as pointer, key and
system are only the beginning. Future packages are expected for clipboard
access, drag and drop, gps positions and so on.
To keep the number of top-level packages under control, move such I/O packages
to the new `io` directory.
The `system` package name was the previous solution to keeping the number of
top-level packages under control: I named it `system` instead of the narrower
`profile` because I expected to put all the less common events into it, turning
`system` into a "package util" smell.
With `io`, package system can be renamed to `profile`.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
The Queue interface was changed from
type Queue interface {
Events(k Key) []Event
}
to the more complex single-step protocol
type Queue interface {
Next(k Key) (Event, bool)
}
to cater for a particular use case: Editor's SubmitEvent. When a
SubmitEvent is passed to a caller of Editor.Next, the Editor state,
in particular the current text, must not have changed by edits
later in the command stream. For example, pressing the keys <E>,
<Enter>, <E> should result in a SubmitEvent where the Editor has
a single 'e' in Text(), not two.
However, there is no reason to push the more complex Queue to every user.
Rather, store remaining input events inside Editor and process them as
Editor.Event (or Layout) is called.
Finally, revert the Queue interface to the simpler Events method.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Elias Naur