Re: Select completions from the minibuffer

[Juri Linkov]

>> Here is a non-intrusive patch that doesn't change the default behavior
>> while provides navigation of completions from the minibuffer
>> like web browsers do on their address bar.
>
> [...]
>
>> +  "M-<up>"    #'minibuffer-completion-previous
>> +  "M-<down>"  #'minibuffer-completion-next
>> +  "M-RET"     #'minibuffer-completion-choose)
>
> If I'm reading this patch correctly, then this looks like just what I've
> wanted for decades.  😀
>
> [...]
>
>> +    (choose-completion nil t t)))
>
> But this doesn't seem quite correct?  The function only takes a single
> parameter...  Or is that part of the patch missing?

Oops, it depends on another patch:

diff --git a/lisp/simple.el b/lisp/simple.el
index accc119e2b..65fc2c94a3 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -9039,6 +9039,7 @@ completion-list-mode-map
     (define-key map [follow-link] 'mouse-face)
     (define-key map [down-mouse-2] nil)
     (define-key map "\C-m" 'choose-completion)
+    (define-key map [C-return] 'choose-completion-no-auto-exit)
     (define-key map "\e\e\e" 'delete-completion-window)
     (define-key map [remap keyboard-quit] #'delete-completion-window)
     (define-key map [left] 'previous-completion)
@@ -9151,10 +9152,12 @@ next-completion
     (when (/= 0 n)
       (switch-to-minibuffer))))
 
-(defun choose-completion (&optional event)
+(defun choose-completion (&optional event no-exit no-quit)
   "Choose the completion at point.
-If EVENT, use EVENT's position to determine the starting position."
-  (interactive (list last-nonmenu-event))
+If EVENT, use EVENT's position to determine the starting position.
+With the prefix NO-EXIT, insert the completion at point to the minibuffer
+and quit the completion window without exiting the minibuffer."
+  (interactive (list last-nonmenu-event current-prefix-arg))
   ;; In case this is run via the mouse, give temporary modes such as
   ;; isearch a chance to turn off.
   (run-hooks 'mouse-leave-buffer-hook)
@@ -9162,6 +9165,7 @@ choose-completion
     (let ((buffer completion-reference-buffer)
           (base-position completion-base-position)
           (insert-function completion-list-insert-choice-function)
+          (completion-no-auto-exit (if no-exit t completion-no-auto-exit))
           (choice
            (save-excursion
              (goto-char (posn-point (event-start event)))
@@ -9179,7 +9184,8 @@ choose-completion
 
       (unless (buffer-live-p buffer)
         (error "Destination buffer is dead"))
-      (quit-window nil (posn-window (event-start event)))
+      (unless no-quit
+        (quit-window nil (posn-window (event-start event))))
 
       (with-current-buffer buffer
         (choose-completion-string
@@ -9189,6 +9195,14 @@ choose-completion
              (list (choose-completion-guess-base-position choice)))
          insert-function)))))
 
+(defun choose-completion-no-auto-exit (&optional event)
+  "Insert the completion at point to the minibuffer without exiting it.
+Like `choose-completion', it chooses the completion at point,
+inserts it to the minibuffer, but doesn't exit the minibuffer."
+  (interactive (list last-nonmenu-event))
+  (let ((completion-no-auto-exit t))
+    (choose-completion event)))
+
 ;; Delete the longest partial match for STRING
 ;; that can be found before POINT.
 (defun choose-completion-guess-base-position (string)