how to invoke a prefix keymap?

[introom]

I want to invoke evil-window-map as a hydra head?

Is it possible?

[abo-abo]

You can use something like this:

(require 'evil)
(require 'which-key)
(eval
 `(defhydra hydra-evil-window-map (:columns 2)
    ,@(mapcar (lambda (x)
                (list (car x) (intern (cdr x)) (cdr x)))
              (which-key--get-keymap-bindings evil-window-map t))
    ("q" nil "quit")))

[shadowrylander]

@introom hercules.el may also suit your needs here!