`Shift + ESC` in key binding

Question

I would like to bind #'window-toggle-side-windows to the key combination shift and escape. That is hammered into my muscle memory by decades of using Intellij.

The obvious (global-set-key "s-ESC" #'window-toggle-side-windows) does not work as expected. It fails recognize the key combination of shift escape.

I am mainly interested in having this work in GUI emacs.

Edit: (global-set-key "S-<escape>" #'window-toggle-side-windows) doesn't work either.

Answer 1

When defining keybindings in Emacs, it is generally easiest to lookup their 'string representations' pressing C-h k followed by pressing the key chords you would like to bind.¹ You will see the 'string representation' in the beginning of the help window. Subsequently, you can simply wrap it with kbd and use it in define-key or global-set-key etc. as follows:

(global-set-key (kbd "S-<escape>") #'window-toggle-side-windows)

For some reason, even when knowing about this, this information is still not straightforward to find on the web or within the Emacs documentation. Therefore, I am repeating this answer here.

From Emacs version >= 29, one can use keymap-set in which wrapping the string representation with kbd is not required anymore.

_{1. As ESC is a prefix key by default, using C-h k does not work directly here. In that case you could try pressing M-: (read-key "Press key (chord): ") followed by the key (chord), to obtain the string representation.}