Recently, I came across this reddit post on which-key. I think Sacha mentioned it in one of her weekly Emacs News posts too. The post reminded me that Kaushal Modi had recommended that I try it out after I’d mentioned that I was using guide-key for the same thing.
I finally got around to installing it from Melpa and giving it a spin. Right now I’m using the default install without any customization. The first thing you notice is that you don’t have to specify which keys to pop up help for; it gives you a prompt for any key sequence if you don’t finish typing it within a second.
The second thing you notice is that the display is nicer looking than guide-key‘s. If things like that matter to you, you should take a look at screen shots from which-key‘s GitHub page. Notice that you can configure both the placement and the font faces of the pop up.
I was happy with guide-key but I also like which-key and will probably leave it installed. It seems a bit snappier than guide-key but that might just be a matter of the idle delay time. If you aren’t using either, I encourage you to try them out.They’re perfect for bindings like 【Ctrl+x r】 which have lots of seldom used completions.