How to create keybindings for the ex/command vim prompt? (cnoremap)


Not sure if this is the appropriate place to ask this question. If not, please, let me know where to ask it.

I would like to use vim with the shell/emacs keybindings for the prompt (ex command), just as I have in my vim/.vimrc:

cnoremap <C-a> <Home>
cnoremap <C-f> <Right>
cnoremap <C-b> <Left>

Also, when I press <C-a> it selects the whole prompt text (like select all). Impossible to unmap that as well.

What would be the appropriate way?