Next, let's look at the various ways that Vim can do autocomplete.

So the first is to autocomplete using a symbol or string in the current buffer. So, one line below, you see userSession. So I'm going to start typing that.

And now I press tab to select it. You can see in the overlay, there is a right-hand column with [buffer] inside it. That means the source for this autocomplete suggestion is the current buffer.

(And there you go, I’m going to get rid of it.)

The next type of autocomplete, a very common one, is to autocomplete based on functions or classes that are anywhere in the codebase. I'm doing this via universal Ctags, and basically remember we had a function called mark{X}, I think markAsSeen. Yeah, there you go.

So I can tab through it and you can see these are sourced from tags. So here we go. I've got this one here, It's going to turn red because I haven't imported this (but we don't need this here so I'm just going to delete it).

The third type of autocomplete worth looking at is a filename auto-completion. So what I can do here is -- just by specifying a file name -- Vim will autocomplete that. You can see here, we've got discounts.js suggested as a file. That's very handy for imports and that kind of thing.

Now, let's move on to the fourth and probably the most exotic type of autocomplete: line-based autocompletion.

Now, imagine for whatever reason, I'm creating a function that's sort of similar to the one below. And I want that line return configFor(..) and then I'll change the argument. So I’ll just start typing return, and then c and I press ctrl-x ctrl-l for line-based autocomplete. And now I can just grab that one there. And bingo, I've got it. I can go and change this as I please.

(I don't really want this so I'm just going to delete all that.)

Now the very last type of autocompletion here is dictionary-words autocompletion.

So let's say I want to print out the message 'Vim is awesome', but I don't want to type the rest of the ‘awes’, I'm lazy like that. So here I press ctrl-x ctrl-k and populate it with words from the dictionary, just like that.

Oh wait, I nearly forgot the most important of all the autocomplete functionalities in a modern Vim setup: the Language Server Protocol autocomplete. So to demonstrate that I'm going to open up my Product class from the Ruby on Rails side of my codebase. And then in a vertical split, I'm going to open up a completely blank new Ruby file. Now, in the left pane, I'm going to instantiate a product in Ruby, which is Product.new. Next, I'm going to call . on this product instance. And as you can see all these methods that are available in the Product class in the right-hand pane are now available, and sometimes they're even arguments like the defaults given within this overlay.

See you next time.