decouple getters from setters about clipboard-sync HOT 1 OPEN

bbac459

I came up with a compromise approach that still links inputs to outputs but doesn't bother trying to hybridize displays. It just finds all the x11 and wayland displays using the standard approaches to access those displays without any fancy attempts to create hybrids that work for known specific displays like mutter. So far this looks good enough because if a wayland compositor does not support the wayland standard, it seems to support the x11 clipboard. Treating mutter as x11 works just as well as treating it as a hybrid (or possibly better since calling the wl-paste cli has some weird behaviors).

This is slightly less flexible than the proposed solution because it can't handle these situations:

1. a display only works with inputs from one implementation and outputs from another implementation,
2. either a getter or setter exists on its own without any known complement

1 should be doable but it is more complicated so I didn't bother with it yet. I'll leave this issue open to address that approach later.

2 might actually be the easiest approach if you just ignore how any displays are linked together, but that's not optimal because you end up with duplicates. So there should at least be some round of optimization that checks for linkages between inputs and outputs and checks for duplicate representations of displays.

Then there's a question for 2, whether we should be including getters and setters that can be instantiated and called without error, even if they don't appear to be connected to any complementary setter or getter. Would there ever be a real clipboard that has this pattern? Or is it more likely that we'd just be calling useless functions that simply return because the library designer decided to return Ok(()) even if the clipboard doesn't exist? This could actually result in monitoring hundreds of imaginary clipboards that don't exist when there are only a couple clipboards on the machine. So I'm inclined not to include this feature unless there is a known concrete benefit.

from clipboard-sync.