> As far as I know, there is no other editor with this capability.
Well, to some degree Vim can do this too. It doesn't let you "eval" a function you just typed into a buffer, but it can eval a vimscript file that you just edited. Including the vimrc, but just like Emacs' init.el reloading it doesn't actually reset the state. But where Vim can't just eval a whole function you can write very complex keybindings on the fly in a much simpler syntax, which made up for it in a few situations for me.
And it's very similar in how the configuration and plugins work - it's all just a scripting language spread across files, and instead of having separately developed plugins you just write a function and run it, more or less.
Emacs is more flexible still, but with its own quirks.
Well, to some degree Vim can do this too. It doesn't let you "eval" a function you just typed into a buffer, but it can eval a vimscript file that you just edited. Including the vimrc, but just like Emacs' init.el reloading it doesn't actually reset the state. But where Vim can't just eval a whole function you can write very complex keybindings on the fly in a much simpler syntax, which made up for it in a few situations for me.
And it's very similar in how the configuration and plugins work - it's all just a scripting language spread across files, and instead of having separately developed plugins you just write a function and run it, more or less.
Emacs is more flexible still, but with its own quirks.