How to disable the buffer with completion options after hiting `tab` in Slime's REPL?

Question

I have been using company for tab completion. It has been great while editing files.

Unfortunately, when I am using a buffer with the SLIME's REPL something annoying happens. As I start typing some function name, e.g.: list-bookmarks, Emacs creates a new buffer showing this info:

Click on a completion to select it.
In this buffer, type RET to select the completion near point.

Possible completions are:
list-bookmarks
list-bookmarks-after-hook
list-bookmarks-before-hook

Almost always, I will ignore this information. Thus, I would like to disable it.

I would like to have only company working on SLIME's REPL. It is already being shown in the status bar as an active mode.

Observation: this "problem" does not if I use M-/. It only happens if I use tab. Since I am a heavy user of tab, I would like to tweak it without chaning bindings on M-\·

My bet is that I need to disable some hook in my config. Is my instinct correct? What exactly should I do?

Thanks!

Answer 1

There are lots of things to unpack here. Let me reframe what you're actually asking.

I have been using company for tab completion.

You have been using company for completion. Company-mode is a minor mode. It can be enabled locally or globally. You don't press any key for the completion to start. You simply wait company-idle-delay seconds, and it starts completing (i.e. the drop-down menu appears). Notice, however, that there's a company-active-map. That's a set of keybindings enabled IF AND ONLY IF the completion has already started. Indeed, (by default) hitting TAB runs company-complete-common. Let me make this clear: hitting TAB BEFORE the completion runs completion-at-point, i.e. the built-in (extremely powerful and underrated) Emacs completion system.

Although company is part of emacs, there's no documentation (afaik). How did I study it? By reading the source code. If you're unsure where to start: visit its homepage; M-x find-library RET company RET; C-h f company-mode RET.

Now it should be clear that what you're really asking is: is there a way to disable the built-in Emacs completion? Well, yes. Do you really need that? No. Don't hit TAB before company starts doing its thing. If you'd like it to start faster, tweak company-idle-delay.

Notice that you don't need to use M-/ when company-mode is active. What M-/ suggests is part of company's completion. In proper terms, dabbrev is a company backend by default.