Register Basics

So lets copy the following line

foo

Now type in :reg

Notice that foo appears two times. We are seeing foo twice because foo is in our first register and our implicit register. Our first register is denoted with 0 (0th may be better term) and implicit is ".

Paste with p 3 times

foo foo foo

highlight and yank all three foos. Lets resee what is in our :reg. Notice that we replaced our implicit register and our 0th register.

Why didnt 0 become 1?

Go back up to a line with foo and delete 1. What just happened? Inspect your :reg

Delete a few more lines and re-inspect your register. What you should observe, and can be found in :h reg is that your implicit register " is always the latest yank or delete. It is also what is used when pasting. We knew this from our previous lesson, but now we observe why.

How do we interact with registers?

We see how our actions are side effects to the state of the registers. But what if you wanted to paste or yank explicitly? Good thing we have a clue. Notice that every register starts with ". Lets :h "

So lets yank into our a register. Move to the line below and type V"ay

foofoofoo

Now lets inspect our registers.

How do we paste from a register?

Lets do something crazy

Copy, paste, and increment the number below 3 times using a macro

Now lets check registers. What do you see? Is your mind blown? What does this mean we can do?