How to rebind C-backspace in projectile find file?

Question

I've installed helm and projectile modes and I wanted to restore the previous behaviour of the C-backspace binding to kill whole last word.

In these modes, when looking for a file (after pressing C-x-f), this binding is changed to turn on/off auto expansion (it seems to run the helm-ff-run-toggle-auto-update function).

I've put this in my init.el:

(define-key helm-find-files-map (kbd "<C-backspace>") 'backward-kill-word)
(define-key helm-projectile-find-file-map (kbd "<C-backspace>") 'backward-kill-word)

And when I run describe-variable for helm-find-files-map and helm-projectile-find-file-map they indeed contain the (C-backspace . backward-kill-word) entry.

Unfortunately, pressing C-backspace in helm-find-file still toggles auto expansion instead of deleting the last path entry. How to achieve this?

---

This is the minimal example of init.el contents that should reproduce this behaviour:

(require 'package)
(add-to-list 'package-archives
         '("melpa" . "http://melpa.milkbox.net/packages/") t)
(package-initialize)

(require 'helm)
(require 'helm-config)

(projectile-global-mode)
(setq projectile-completion-system 'helm)
(helm-projectile-on)

(helm-mode 1)

(define-key helm-find-files-map (kbd "<C-backspace>") 'backward-kill-word)
(define-key helm-projectile-find-file-map (kbd "<C-backspace>") 'backward-kill-word)

Answer 1

With helm-mode enabled, the ordinary find-file command will use helm-read-file-map, so you should use:

(define-key helm-read-file-map (kbd "<C-backspace>") #'backward-kill-word)

But if you are using helm, helm-find-files provides more features than find-file so you are suggested to use the former.