Why huge maps twice: KEYToString and KEYNames? about go-evdev HOT 4 CLOSED

I think commenting that is a great idea, I made required changes in #15
We can't easily comment specific XNames block, but there is a comment at the begging of XNames sections, should be sufficient.

from go-evdev.

@guettli
Because different names can point to the very same keycode (for example KEY_DIRECTION and KEY_ROTATE_DISPLAY points to the same code number), table has been split for string conversion and debug information separately.

First map KEYToString provides only one name for given keycode (first found in header files), this is used for conversion from keycode to string representation that can be easily reversed later with KEYFromString (XFromString actually provides conversion for all keycode aliases by the way).

KEYNames However, provides all aliases separated with slash, its purpose is debug/information only.
as an example:

KEY_ALL_APPLICATIONS: "KEY_ALL_APPLICATIONS/KEY_DASHBOARD",
KEY_COFFEE: "KEY_COFFEE/KEY_SCREENLOCK",
KEY_ROTATE_DISPLAY: "KEY_ROTATE_DISPLAY/KEY_DIRECTION",
KEY_BRIGHTNESS_AUTO: "KEY_BRIGHTNESS_AUTO/KEY_BRIGHTNESS_ZERO",
BTN_GAMEPAD: "BTN_GAMEPAD/BTN_SOUTH/BTN_A",
BTN_NORTH: "BTN_NORTH/BTN_X",
BTN_WEST: "BTN_WEST/BTN_Y",

You can argue if two tables has some real value in the library, for many usecases KeyToString representation is good enough. It was my idea to make it that way, memory cost of such additional table is negligible but on the other hand it adds a little bit of complexity at generating process.

from go-evdev.

@gethiox Thanks for answering this one.
@guettli Let me know if that answer satisfies you and the issue can be closed.

from go-evdev.

@gethiox thank you for the explanation. I had a rough look at both maps, and overlooked entries like "KEY_COFFEE/KEY_SCREENLOCK".

Why not add a comment like this, to make it more clear:

// KEYNames maps from EvCode to a string.
// If one EvCode has two string representations, both are seperated by a slash.
// Example: KEY_COFFEE: "KEY_COFFEE/KEY_SCREENLOCK"
var KEYNames = map[EvCode]string{
...

I think this would help new users to understand that.

I could create a PR, but feel free to just do it yourself - whatever is more convenient for you.

from go-evdev.