WEBVTT

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Okay, cool. So, welcome to the third

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lecture of the missing semester of your

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si a second today we're going to be

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talking about text editors this is a

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topic that I really like I think it's

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one of the most valuable topics that

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we're teaching in this class because as

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programmers you spend so much of your

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time editing text editing programs that

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if you invest time into making yourself

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more efficient at doing this you'll save

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a ton of time probably hundreds of hours

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over the course of your undergrad or

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over the course of your career so text

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editors are a little bit different than

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other programs you might use to edit say

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things like English prose because

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programming is different than writing

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English prose when you're programming

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you spend a lot of time reading what

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you've written you spend a lot of time

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navigating around a buffer and you spend

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a lot of time making little edits to

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code all over the place rather than just

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writing in a long stream like you do

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when you're writing an essay or

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something and so it makes sense that

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there different programs for these

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different purposes right so yeah things

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like Microsoft Word for writing essays

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and things like vim and Emacs and vs

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code and sublime for writing code so the

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way you learn a text editor and become

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really good at it is you start with a

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tutorial and so that's basically going

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to be the function of today's lecture

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plus the exercises we've given you and

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then after the tutorial you need to

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stick with the editor for all your

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editing tasks and when you're learning a

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sophisticated tool so today we're going

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to teach you vim which is one powerful

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editor that a lot of programmers use

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when you're learning such a

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sophisticated tool it may be the case

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that initially switching to this tool

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slows you down a little bit when you're

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programming but stick with it because

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I'd say that in about 20 hours of

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programming using a new editor you'll be

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back to the same speed at which you

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programmed using your old tool and then

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after that the benefits will start and

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you'll get faster and faster as you

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learn more with these sophisticated

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programs like them it takes not way too

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long to learn the basics but a lifetime

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to master and so throughout the time

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you're using this tool make sure you

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look things up as you go if you ever get

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to a point where you're like oh this is

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a really inefficient way of doing things

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is there a better way the answer is

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almost always yes because these text

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editors were written by programmers for

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programmers and so of course like the

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peep

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I wrote these tolls ran into the same

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kinds of issues and fixed them so that

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you don't need to deal with these

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anymore and so yeah as you're learning

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make sure you look things up as you go

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either use Google or feel free to send

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us emails if you have questions or come

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to office hours and we'll help you

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figure out how to do things really fast

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so as far as which editor to learn in

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previous iterations of this class we

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actually avoided teaching a specific

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editor because we didn't want to enforce

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our opinions on you guys but we actually

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think that it's really useful to teach

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you how to use one particular tool and

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use it well and so people have really

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strong opinions about editor so you can

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see the course notes for more links on

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this topic looking at which editors have

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been popular over the years Stack

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Overflow I'm sure you've all heard of

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that does a survey every year asking

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developers various questions and one

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thing to ask is which TextEdit Derk do

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you use and it seems to be that

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currently the most popular kind of

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graphical editor is vs code and the most

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popular editor that is based within a

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command line interface is vim and so

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we're going to be teaching you vim and

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there a couple reasons for this one is

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that all the instructors so me John and

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Jose use vim as our primary editor and

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we've been doing this for many years and

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we've been very happy with it

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and we think that there are a lot of

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interesting ideas behind them so even if

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you don't end up using this particular

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tool in the long term I think it's

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valuable to learn these ideas and also a

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lot of tools have actually been really

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excited about the ideas in vim and so

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they support a vim emulation mode for

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example vs code what's apparently the

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most popular editor in use today

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supports vim bindings and this vim

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emulation mode as of now has like 1.4

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million downloads and as you'll see over

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the course of this lecture a lot of

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different tools like including your

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shell including things like the Python

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repple and like Jupiter notebook and all

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sorts of other things even your web

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browser can support of emulation mode

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and so yeah we're going to be teaching

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you this really neat tool today and in

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this lecture we can't really cover all

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of them right it's a very powerful tool

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but our goal is to teach you and the

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core philosophy of them like the really

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neat ideas behind it and then in

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addition to that some of the basics like

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how do you open a file close a file

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navigate around a file make edits and

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things like that and

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you may not remember every single little

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detail from this lecture because we're

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gonna go pretty fast through some of the

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material but it's all in the lecture

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notes and then the exercises actually

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give you links to some tutorials and

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things so I highly recommend that you

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actually go through all the exercises at

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least the non advanced exercises any

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questions so far great okay so one of

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the really cool ideas behind them is

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that vim is a modal editor what does

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this mean modal comes from the word mode

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and this means that vim has multiple

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operating modes and this is kind of

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developed from the idea that when you're

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programming there often times where

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you're doing different types of things

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like sometimes you're reading code

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sometimes you're making small edits to

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code like you're finding a particular

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point like changing a little thing

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somewhere sometimes you're just writing

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a lot of code in one go like suppose

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you're just writing a function from

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scratch and so there's different

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operating modes for doing these

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different types of things and so I'm

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actually want to write this down on the

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blackboard so I'll have a useful thing

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to refer to later so when you start vim

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up it starts up in what's called normal

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mode and in this mode all the different

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key combinations behave in one way and

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then there are different key

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combinations that switch you between

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normal mode and other modes which change

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the meaning of different keys so for the

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most part you'll be spending most of

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your time in vim in normal mode or what

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is called insert mode and to go to

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insert mode you press the key I for

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normal mode and to go from insert mode

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back to normal mode you press the Escape

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key a little note on notation because

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we'll need this later in the notation

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I'm going to be using in this lecture

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and what's also in the lecture notes and

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what vim uses to give you feedback they

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have a couple different ways of talking

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about different keys so when they're

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talking about bare keys like just the

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eye key on your keyboard they'll just

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say eye but for a different key

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combinations like when you press control

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and something like say control V it's

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notated in one of like approximately

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three ways one way that can be notated

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is a caret and then the control

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character so this is control V another

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way this might be written I think we've

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written it this way in

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lecture notes as control-v this is

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probably the one you're more used to

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seeing and then in some parts of them

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this is written as angle brackets C - V

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close angle bracket so just a little bit

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of notation that will be useful later

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so yeah vim has a couple different modes

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where normal mode is designed for

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navigating around a file reading things

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going from file to file things like that

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and then insert mode is where you type

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in text so most keys that you press here

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will just go into your text buffer where

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as keys that you press here are not

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being put into the buffer and instead

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are used for things like navigation or

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making edits and actually the picture is

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a little bit more complicated than this

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there are a whole bunch of other modes

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and I'm just gonna write them down here

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because we'll have them here to refer to

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later and so if it also has a replace

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mode for rather than inserting text and

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kind of pushing what's ahead of it

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forward it will overwrite text and then

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it has a bunch of different modes for

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selection so it has a mode called visual

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mode and then it has visual line and

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visual block this one is enter via the R

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key this was entered via the V key this

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one is entered via shift B and this one

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is entered via control V and then

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there's the command line mode which is

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entered via the colon key

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okay so now that we have that on the

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board to refer to later we can actually

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try some of this out all right so one

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thing we noticed looking at that picture

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is that to go from normal mode to any of

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the other modes we press some key but to

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go from any of the other modes back to

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normal mode where we spend a lot of our

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time we use the Escape key on our

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keyboard so for this reason since you

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under pressing the Escape key a lot when

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using vim a lot of programmers rebind

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one of the keys on their keyboard to be

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escape because it's really inconvenient

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to reach up with your left pinkie to

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press that tiny little Escape key in the

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corner of your keyboard and so a lot of

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people use the caps lock key instead so

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it's right there in the home row and we

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have some links in the lecture notes for

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how you can do this key rebinding okay

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so now that we've talked about kind of

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one of the core ideas of vim the idea of

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modal editing we can talk about some of

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the basics like how do you open up this

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text editor how do you open file save

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files and things like that and so this

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is a command line based program although

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there are some graphical variants and

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the way you start this program is by

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running vim one thing you might notice

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is that in the bottom left corner of my

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screen they actually saw what I just

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typed this will be useful later in this

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lecture where I'm actually typing in

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commands for vim and I'll be saying what

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I'm typing but you'll also see it on the

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screen so if I press ctrl C see it says

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ctrl C over there is that text big

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enough for everybody to read great okay

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so the way we open vim is just by

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running the program vim on our command

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line and this comes pre-installed on

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most systems and if you don't have it

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you can install it using your package

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manager vim can also take an argument if

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we want to use it to edit a particular

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file instead of just opening up the

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program then later opening a file so for

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example I have a file in this directory

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this is actually the lecture notes for

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this lecture so I can do vim editors MD

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and press ENTER and then boom them is

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started and then in this lecture I'm not

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running vim in the completely Exton I've

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configured a couple of things that

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behave a little bit nicer by defaults

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little things like having line numbers

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on the left or having some more status

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information on the bottom and if you

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want to start with this default

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configuration we have a link to this in

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the lecture notes so you can get a

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slightly more sane config by default. So,

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once you've opened Vim, what do you do?

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Well, as I said earlier, Vim starts in

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normal mode, so if I just start typing

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letters like, say, type X it didn't insert

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X into the buffer. You can see the cursor

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up in the top left: it actually deleted

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one of the characters. That's because I'm

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in normal mode, not insert mode. So insert

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mode is basically what you're used to with

00:11:08.620 --> 00:11:10.900
all the other text editors you've used

00:11:09.850 --> 00:11:12.310
in the past, where there's a cursor

00:11:10.900 --> 00:11:15.310
somewhere, you press the character, and it

00:11:12.310 --> 00:11:18.130
just goes into your buffer. I'm instead

00:11:15.310 --> 00:11:19.900
in vim you start a normal mode and you

00:11:18.130 --> 00:11:21.610
can press I to go into insert mode so

00:11:19.900 --> 00:11:23.980
see I've pressed I and then in the

00:11:21.610 --> 00:11:26.500
bottom left notice that it says - -

00:11:23.980 --> 00:11:27.850
insert the bottom left always tells you

00:11:26.500 --> 00:11:29.650
what mode you're in unless this normal

00:11:27.850 --> 00:11:31.270
mode in which case it's blank and now

00:11:29.650 --> 00:11:33.250
that I'm an insert mode if I press the X

00:11:31.270 --> 00:11:35.740
character for example see it just gets

00:11:33.250 --> 00:11:37.450
inserted into my text buffer and I can

00:11:35.740 --> 00:11:39.580
backspace over at type other stuff and

00:11:37.450 --> 00:11:41.400
now my text editor kind of behaves like

00:11:39.580 --> 00:11:43.780
you'd expect any other program to behave

00:11:41.400 --> 00:11:45.520
so from this point how to go back to

00:11:43.780 --> 00:11:48.910
normal mode if I want to stop inserting

00:11:45.520 --> 00:11:51.670
characters. Yes, exactly. I press escape.

00:11:48.910 --> 00:11:53.830
And, that's the symbol my keystroke

00:11:51.670 --> 00:11:58.960
visualizer uses for escape, so

00:11:53.830 --> 00:12:01.150
just be aware of that. And then, Vim has

00:11:58.960 --> 00:12:02.890
this idea, that using the mouse is

00:12:01.150 --> 00:12:04.570
inefficient, like your hands are on the

00:12:02.890 --> 00:12:06.460
keyboard, moving your hand over to the

00:12:04.570 --> 00:12:08.290
mouse takes a lot of time, right, like you

00:12:06.460 --> 00:12:09.610
don't want to waste those couple of

00:12:08.290 --> 00:12:11.410
milliseconds while you're programming,

00:12:09.610 --> 00:12:13.990
like in the middle of things. So, instead,

00:12:11.410 --> 00:12:15.700
all Vim functionality can be accessed

00:12:13.990 --> 00:12:16.780
just through the keyboard. And, it's all

00:12:15.700 --> 00:12:19.330
sorts of things you might be used to

00:12:16.780 --> 00:12:21.460
doing like opening files by going, like,

00:12:19.330 --> 00:12:23.050
file open, or file save, or things like

00:12:21.460 --> 00:12:25.450
that, or instead access through the

00:12:23.050 --> 00:12:27.520
keyboard. And, how is that done? That's

00:12:25.450 --> 00:12:28.690
done through one of the other Vim modes

00:12:27.520 --> 00:12:31.960
that are on the board over there. In

00:12:28.690 --> 00:12:33.850
particular, through command line mode. So,

00:12:31.960 --> 00:12:36.370
if you're in normal mode, and you press

00:12:33.850 --> 00:12:39.370
the ":" key, you'll notice that the

00:12:36.370 --> 00:12:41.320
cursor - I guess my visualizer is covering

00:12:39.370 --> 00:12:43.060
the thing right now but it's gone - the

00:12:41.320 --> 00:12:46.110
cursor jumps to the bottom - the bottom

00:12:43.060 --> 00:12:48.510
left - and it shows that ":" I just typed.

00:12:46.110 --> 00:12:50.220
Now, I can type in a command. So, you can

00:12:48.510 --> 00:12:51.570
think of this almost like the command

00:12:50.220 --> 00:12:53.160
shell that we've talked been talking

00:12:51.570 --> 00:12:54.029
about over the last few days, except this

00:12:53.160 --> 00:12:55.800
is Vim's

00:12:54.029 --> 00:12:57.200
command shell, so you give Vim commands

00:12:55.800 --> 00:12:59.339
here, instead of shell commands. And

00:12:57.200 --> 00:13:00.600
there are a bunch of built-in commands

00:12:59.339 --> 00:13:02.820
that do all the things that you're used

00:13:00.600 --> 00:13:04.260
to. Like, for example, one command that you

00:13:02.820 --> 00:13:05.670
might want to know is how to quit this

00:13:04.260 --> 00:13:07.440
editor. You might notice that if you're in

00:13:05.670 --> 00:13:08.730
normal mode, I can press "Escape" to go

00:13:07.440 --> 00:13:11.940
back from command line mode to normal

00:13:08.730 --> 00:13:13.560
mode, and I press "control C", unlike what

00:13:11.940 --> 00:13:16.019
happens to a lot of programs, this doesn't

00:13:13.560 --> 00:13:18.360
quit Vim. So, how do I quit Vim? I can

00:13:16.019 --> 00:13:19.860
press ":", and then go into command

00:13:18.360 --> 00:13:23.430
line mode, and then I can type in the

00:13:19.860 --> 00:13:24.870
command "quit". "Q-U-I-T". You'll see that I

00:13:23.430 --> 00:13:28.560
- maybe I should move this over to the

00:13:24.870 --> 00:13:31.350
middle or something - see, it says ":quit"

00:13:28.560 --> 00:13:32.910
and I press ENTER, and it quits Vim. I can

00:13:31.350 --> 00:13:35.490
open Vim up again. There's actually a

00:13:32.910 --> 00:13:38.430
short form for this command, just ":q", and

00:13:35.490 --> 00:13:40.019
that'll do the same thing. And, there are a

00:13:38.430 --> 00:13:42.839
bunch of other useful commands like this.

00:13:40.019 --> 00:13:45.149
So, some other handy ones to know are

00:13:42.839 --> 00:13:47.790
how do you save a file? So, suppose I make

00:13:45.149 --> 00:13:51.420
some edits here, like "hello world".

00:13:47.790 --> 00:13:53.970
So, I pressed "i" to go into insert mode - or

00:13:51.420 --> 00:13:55.560
let me redo that - I press "i" to go into

00:13:53.970 --> 00:14:02.010
insert mode. Right now, I can use the down

00:13:55.560 --> 00:14:03.240
arrow to... I think I've slightly I

00:14:02.010 --> 00:14:07.019
should fix that. Can you fix the config,

00:14:03.240 --> 00:14:11.730
actually, John? Never mind that.

00:14:07.019 --> 00:14:14.820
Okay, so, suppose I go down to this line,

00:14:11.730 --> 00:14:17.010
and I press "i" to go into insert mode, and

00:14:14.820 --> 00:14:18.930
type in some text, and then press "escape"

00:14:17.010 --> 00:14:20.610
to go back to normal mode. Now, how do I

00:14:18.930 --> 00:14:22.680
actually save this file? Well, there's

00:14:20.610 --> 00:14:25.550
another command for that. So, ":" to go

00:14:22.680 --> 00:14:30.480
into command mode, and then I can type "W"...

00:14:25.550 --> 00:14:33.240
...and press "Enter". "W" stands for write. And,

00:14:30.480 --> 00:14:35.699
it says in the bottom "editors.md"

00:14:33.240 --> 00:14:37.829
whatever blah blah written. And, so, this

00:14:35.699 --> 00:14:40.320
means it saved the file and so now if I

00:14:37.829 --> 00:14:42.209
":q" to quit and open the same file,

00:14:40.320 --> 00:14:46.850
again, you'll see that the changes have

00:14:42.209 --> 00:14:49.019
been persisted. There are a couple other

00:14:46.850 --> 00:14:50.130
there's... So, there's a ton of different

00:14:49.019 --> 00:14:53.070
Vim commands that are useful for

00:14:50.130 --> 00:14:56.100
different reasons. But, I'll just explain

00:14:53.070 --> 00:14:59.070
a couple more to you now. One command

00:14:56.100 --> 00:15:01.500
that's really useful is help. ":help"

00:14:59.070 --> 00:15:04.080
And you can do ":help", and then type in a

00:15:01.500 --> 00:15:06.090
particular key, or a particular command,

00:15:04.080 --> 00:15:08.580
and get help for that keystroke or that

00:15:06.090 --> 00:15:10.950
command. So, if I want to know what

00:15:08.580 --> 00:15:15.420
":w" does, I

00:15:10.950 --> 00:15:21.300
can do : help : W, and that'll give me

00:15:15.420 --> 00:15:23.160
the documentation on : w or : write. If I

00:15:21.300 --> 00:15:25.560
do : q, it'll close this window and bring

00:15:23.160 --> 00:15:28.530
me back to where I was before.

00:15:25.560 --> 00:15:35.340
And, notice that ":help :w" is different

00:15:28.530 --> 00:15:38.190
from ":help w", because the W key is the W

00:15:35.340 --> 00:15:40.590
that, like, when you're in normal mode and

00:15:38.190 --> 00:15:41.670
press W, what happens is just the W key

00:15:40.590 --> 00:15:43.530
here without the ":".

00:15:41.670 --> 00:15:50.340
And, if I look for help for ":w", that's

00:15:43.530 --> 00:15:56.040
the help for the W command. So, now you

00:15:50.340 --> 00:15:58.110
basically have the bare fundamentals

00:15:56.040 --> 00:16:00.720
needed to use them. right? You can open

00:15:58.110 --> 00:16:03.180
the editor, use it to edit a particular

00:16:00.720 --> 00:16:05.010
file, press "i" to go into insert mode and

00:16:03.180 --> 00:16:06.840
type in some text, press "escape" to go

00:16:05.010 --> 00:16:09.630
back to normal mode, and then :w to save

00:16:06.840 --> 00:16:11.460
your changes, :w to quit. So, like already

00:16:09.630 --> 00:16:13.920
you have the bare fundamentals necessary

00:16:11.460 --> 00:16:17.210
to edit files using Vim, albeit somewhat

00:16:13.920 --> 00:16:23.700
inefficiently. So, any questions so far?

00:16:17.210 --> 00:16:25.470
Yeah in the back. Yeah so the question is,

00:16:23.700 --> 00:16:27.060
What's the benefit of the

00:16:25.470 --> 00:16:28.590
normal mode? And, we'll talk about that in

00:16:27.060 --> 00:16:31.560
more detail, in like five minutes.

00:16:28.590 --> 00:16:33.030
But, in short, insert mode is just for

00:16:31.560 --> 00:16:34.920
typing in text. So, I'm in insert mode, I

00:16:33.030 --> 00:16:36.270
can type in text. But, when I'm

00:16:34.920 --> 00:16:39.000
programming, I actually spend a lot of

00:16:36.270 --> 00:16:40.590
time moving around my file making small

00:16:39.000 --> 00:16:42.210
little changes. So, I go here and like, oh

00:16:40.590 --> 00:16:45.390
maybe I want to change this HTTPS link to

00:16:42.210 --> 00:16:48.120
an HTTP.

00:16:45.390 --> 00:16:49.920
I can make like small point edits, things

00:16:48.120 --> 00:16:51.120
like that, in normal mode. And we'll see a

00:16:49.920 --> 00:16:52.920
whole lot more of that in about five

00:16:51.120 --> 00:16:59.130
minutes. Good question!

00:16:52.920 --> 00:17:05.070
Any other questions? Okay cool. So, moving

00:16:59.130 --> 00:17:11.100
along, one other thing that's kind of

00:17:05.070 --> 00:17:12.720
useful to know, I think, is, at a high

00:17:11.100 --> 00:17:15.479
level, Vim's model of

00:17:12.720 --> 00:17:16.470
buffers versus windows versus tabs. So,

00:17:15.479 --> 00:17:17.939
it's probably the case that whatever

00:17:16.470 --> 00:17:19.829
program you were using before, like

00:17:17.939 --> 00:17:21.899
Sublime Text or VS Code or whatever,

00:17:19.829 --> 00:17:23.249
you could open multiple files in it,

00:17:21.899 --> 00:17:24.899
right, and you could probably have

00:17:23.249 --> 00:17:27.449
multiple tabs open and have multiple

00:17:24.899 --> 00:17:29.129
windows open of your editor. So, Vim also

00:17:27.449 --> 00:17:31.200
has a notion of those different things.

00:17:29.129 --> 00:17:34.379
But, its model is a little bit different

00:17:31.200 --> 00:17:36.359
than most other programs. So, Vim

00:17:34.379 --> 00:17:38.340
maintains a set of open buffers - that's

00:17:36.359 --> 00:17:40.320
the word it uses for open files - and so,

00:17:38.340 --> 00:17:42.239
it has a set of open files, and then kind

00:17:40.320 --> 00:17:44.489
of separately from that, you can have a

00:17:42.239 --> 00:17:46.619
number of tabs, and tabs can have windows.

00:17:44.489 --> 00:17:47.460
The kind of weird thing which makes Vim

00:17:46.619 --> 00:17:48.899
a little bit different than the

00:17:47.460 --> 00:17:50.729
program you've probably used in the past is

00:17:48.899 --> 00:17:52.049
that there isn't necessarily a

00:17:50.729 --> 00:17:55.200
one-to-one correspondence between

00:17:52.049 --> 00:17:56.669
buffers and windows. So, one thing I can

00:17:55.200 --> 00:17:58.259
do, for example, here - and we'll show you

00:17:56.669 --> 00:18:00.989
the key combinations and stuff for this

00:17:58.259 --> 00:18:02.220
later - but one thing you can do is create

00:18:00.989 --> 00:18:04.109
two different windows. So, I have one

00:18:02.220 --> 00:18:07.139
window up here, and then one window down

00:18:04.109 --> 00:18:08.609
here. And, notice that the same files open

00:18:07.139 --> 00:18:10.529
in both windows. So, if I make some edits

00:18:08.609 --> 00:18:11.759
over here, they actually happen in the

00:18:10.529 --> 00:18:13.729
bottom window, as well, because it's the

00:18:11.759 --> 00:18:14.412
same buffer that's open in both windows.

00:18:14.412 --> 00:18:18.269
And, this is kind of useful, for, say,

00:18:16.590 --> 00:18:19.830
looking at two different parts of a

00:18:18.269 --> 00:18:20.940
single file at the same time. Like, so you

00:18:19.830 --> 00:18:22.919
want to be able to look at the top of a

00:18:20.940 --> 00:18:25.049
file, say at an import to your program,

00:18:22.919 --> 00:18:27.809
while you're down below, working

00:18:25.049 --> 00:18:29.129
somewhere else. So, this is one helpful

00:18:27.809 --> 00:18:32.999
thing to keep in mind, that Vim has this

00:18:29.129 --> 00:18:35.729
idea of - there are a number of tabs, and

00:18:32.999 --> 00:18:38.159
each tab has some number of windows, and

00:18:35.729 --> 00:18:40.649
then each window has, uh, corresponds to

00:18:38.159 --> 00:18:42.269
some buffer. But, a particular buffer can

00:18:40.649 --> 00:18:44.399
be open in zero or more windows at a

00:18:42.269 --> 00:18:45.809
time. Just one thing that confused me

00:18:44.399 --> 00:18:48.049
when I was initially learning Vim, so I

00:18:45.809 --> 00:18:50.669
want to explain that early on. And then,

00:18:48.049 --> 00:18:53.580
the ":q" command, which we talked about

00:18:50.669 --> 00:18:55.349
earlier, is not exactly quit. It's kind of

00:18:53.580 --> 00:18:56.729
"close the current window", and then, when

00:18:55.349 --> 00:18:59.460
there are no more open windows, Vim will

00:18:56.729 --> 00:19:01.320
quit. So, here, if I do ":q", it'll only

00:18:59.460 --> 00:19:03.570
close the window, I think, on the top here

00:19:01.320 --> 00:19:05.609
because that's the one I was in, and, now,

00:19:03.570 --> 00:19:08.159
the remaining window becomes fullscreen.

00:19:05.609 --> 00:19:10.379
I can do : Q again to close this. Now we're in

00:19:08.159 --> 00:19:14.879
the second tab that I'd opened. If I do :Q

00:19:10.379 --> 00:19:16.229
a final time, okay, now, Vim exits. And if

00:19:14.879 --> 00:19:17.940
you don't want to press ":q" way too many

00:19:16.229 --> 00:19:21.419
times... Okay, so, here I have three split

00:19:17.940 --> 00:19:24.589
windows. If I do ":qa", for quit all, it

00:19:21.419 --> 00:19:24.589
closes all the open windows.

00:19:25.370 --> 00:19:30.660
All right, so, now, to answer your question of

00:19:28.650 --> 00:19:32.610
"What is normal mode actually for?" This is

00:19:30.660 --> 00:19:34.080
another, really cool idea in Vim, and I

00:19:32.610 --> 00:19:36.030
think this is actually, like, the most

00:19:34.080 --> 00:19:38.550
fundamentally interesting idea of this

00:19:36.030 --> 00:19:42.000
program. It's that, like, you're all

00:19:38.550 --> 00:19:44.370
programmers, you like programming; Vim has

00:19:42.000 --> 00:19:47.220
this idea that Vim's normal mode, like,

00:19:44.370 --> 00:19:49.740
Vim's interface, itself, is a programming

00:19:47.220 --> 00:19:51.060
language. And, let me repeat that.

00:19:49.740 --> 00:19:52.860
That's like a kind of fundamentally

00:19:51.060 --> 00:19:54.020
interesting idea: the interface is a

00:19:52.860 --> 00:19:56.250
programming language.

00:19:54.020 --> 00:19:57.570
What does that mean? It means that

00:19:56.250 --> 00:19:59.280
different key combinations have

00:19:57.570 --> 00:20:00.150
different effects, and, once you learn the

00:19:59.280 --> 00:20:02.400
different effects, you can actually

00:20:00.150 --> 00:20:03.390
combine them together - just like in a

00:20:02.400 --> 00:20:04.770
programming language - you can learn

00:20:03.390 --> 00:20:05.880
different functions and stuff and then

00:20:04.770 --> 00:20:08.070
glue them all together to make an

00:20:05.880 --> 00:20:09.870
interesting program. In the same way, once

00:20:08.070 --> 00:20:10.980
you learn Vim's different movement and

00:20:09.870 --> 00:20:13.890
editing commands, and things like that,

00:20:10.980 --> 00:20:16.950
you can talk to Vim by programming Vim

00:20:13.890 --> 00:20:19.170
through its interface. And, once this

00:20:16.950 --> 00:20:20.880
becomes muscle memory, you can basically

00:20:19.170 --> 00:20:22.440
edit files at the speed at which you

00:20:20.880 --> 00:20:23.640
think. Like at least for me, I don't think

00:20:22.440 --> 00:20:25.320
I've been able to do this with any other

00:20:23.640 --> 00:20:29.010
text editor that I've used in the past,

00:20:25.320 --> 00:20:31.380
but this one gets pretty close. So, let's

00:20:29.010 --> 00:20:34.170
dig into how exactly normal mode works.

00:20:31.380 --> 00:20:36.140
So, you can try to follow along with this,

00:20:34.170 --> 00:20:38.400
like, open up some random file in Vim, and

00:20:36.140 --> 00:20:40.470
follow some of the key combinations I

00:20:38.400 --> 00:20:42.330
type in. So, one basic thing that you

00:20:40.470 --> 00:20:44.010
might want to do, is just navigate around

00:20:42.330 --> 00:20:46.020
a buffer. Like, move your cursor up/down/

00:20:44.010 --> 00:20:48.510
left/right. And, so the way you do that in

00:20:46.020 --> 00:20:50.700
Vim, is using the hjkl keys, not the arrow

00:20:48.510 --> 00:20:52.050
keys. Though they do work by default, try

00:20:50.700 --> 00:20:53.520
to avoid them, because you don't want to

00:20:52.050 --> 00:20:54.660
have to move your hand all the way over

00:20:53.520 --> 00:20:57.240
to the arrow keys. Like, there's a ton of

00:20:54.660 --> 00:21:00.510
time you're wasting, right? HJKL is right

00:20:57.240 --> 00:21:04.020
on the home row. And, so, J moves down, K

00:21:00.510 --> 00:21:06.390
moves up, H moves left, and L moves right.

00:21:04.020 --> 00:21:08.940
And, this may seem a little unintuitive

00:21:06.390 --> 00:21:10.410
now; there was some historical reason for

00:21:08.940 --> 00:21:13.440
it, like, the keyboard the original vi

00:21:10.410 --> 00:21:14.910
developer used had the hjkl keys, like,

00:21:13.440 --> 00:21:17.040
labeled, and arranged in a way that made

00:21:14.910 --> 00:21:19.260
this more reasonable. But, this will very

00:21:17.040 --> 00:21:20.370
soon become muscle memory. So, this is the

00:21:19.260 --> 00:21:24.270
basic way you can move your cursor

00:21:20.370 --> 00:21:26.070
around while in normal mode. Now, what

00:21:24.270 --> 00:21:27.720
else can you do? Well, if we had to move

00:21:26.070 --> 00:21:29.820
around files like this, it'd be really

00:21:27.720 --> 00:21:31.590
slow. We don't want to have to

00:21:29.820 --> 00:21:33.210
hold down these keys, and like, wait for a

00:21:31.590 --> 00:21:34.350
long time for Vim to do its thing. And

00:21:33.210 --> 00:21:35.760
so, there are all these other, different

00:21:34.350 --> 00:21:36.650
key combinations for doing different

00:21:35.760 --> 00:21:38.120
movements.

00:21:36.650 --> 00:21:39.200
Also, by the way, this is all in the

00:21:38.120 --> 00:21:40.940
lecture notes, so you don't need to

00:21:39.200 --> 00:21:43.550
memorize every single key and its

00:21:40.940 --> 00:21:45.320
meaning right now. Just try to understand

00:21:43.550 --> 00:21:47.570
the overall idea that Vim's interface is

00:21:45.320 --> 00:21:50.000
a programming language. So, another thing

00:21:47.570 --> 00:21:52.820
you can do is press the W key. This moves

00:21:50.000 --> 00:21:54.620
the cursor forward by one word. And then,

00:21:52.820 --> 00:21:57.740
similarly, the "B" key moves the cursor

00:21:54.620 --> 00:21:59.360
backward by one word. So, this allows

00:21:57.740 --> 00:22:01.820
slightly more efficient movement within

00:21:59.360 --> 00:22:04.010
the line. There's also the "E" key for

00:22:01.820 --> 00:22:06.620
moving to the end of a word. I'm going to

00:22:04.010 --> 00:22:08.030
move this over a little bit. So, if I'm

00:22:06.620 --> 00:22:09.800
here, for example, and I press the "E" key

00:22:08.030 --> 00:22:12.850
it'll go to the end of this word, end of

00:22:09.800 --> 00:22:15.980
this word, end of the next word and so on.

00:22:12.850 --> 00:22:17.720
You can also move by whole lines, so zero

00:22:15.980 --> 00:22:19.760
moves to the beginning of a line, dollar

00:22:17.720 --> 00:22:22.640
sign moves to the end of a line, and the

00:22:19.760 --> 00:22:25.790
caret key moves to the first non-empty

00:22:22.640 --> 00:22:31.730
character on a line. So, let me find one

00:22:25.790 --> 00:22:33.590
of those, for example. So, here, my

00:22:31.730 --> 00:22:34.760
cursor's right here; if I press 0, my

00:22:33.590 --> 00:22:37.040
cursor goes to the beginning of the line,

00:22:34.760 --> 00:22:39.590
dollar sign, end of the current line; and

00:22:37.040 --> 00:22:41.270
if I press caret, where, like, on what

00:22:39.590 --> 00:22:44.840
character will the curser end up? Can

00:22:41.270 --> 00:22:47.870
anybody guess? So, caret goes to the first

00:22:44.840 --> 00:22:53.000
non-empty character on a line, kind of

00:22:47.870 --> 00:22:57.200
like Regex caret. Yeah, exactly! It goes

00:22:53.000 --> 00:22:59.780
to this dash. Let's talk about some more

00:22:57.200 --> 00:23:01.220
movement commands. There're ways to

00:22:59.780 --> 00:23:06.230
scroll up and down in a buffer, so

00:23:01.220 --> 00:23:08.510
control U goes up, and control D scrolls

00:23:06.230 --> 00:23:10.850
down. So, this is better than holding down

00:23:08.510 --> 00:23:13.190
the K or J keys, for example. This is a

00:23:10.850 --> 00:23:17.720
lot slower than moving by entire pages.

00:23:13.190 --> 00:23:19.970
Control D and control U. There's also

00:23:17.720 --> 00:23:22.400
ways to move by the entire buffer. So,

00:23:19.970 --> 00:23:26.420
capital "G" moves all the way down... "gg"

00:23:22.400 --> 00:23:28.490
moves all the way up. Some of these

00:23:26.420 --> 00:23:29.600
movement keys are mnemonics; so, they're

00:23:28.490 --> 00:23:31.400
like, a little bit easier to remember for

00:23:29.600 --> 00:23:33.440
that reason, right, like, "W" is word, "B"

00:23:31.400 --> 00:23:36.230
is beginning of word, E is end of word. Those

00:23:33.440 --> 00:23:38.030
all seem pretty logical. 0, caret and

00:23:36.230 --> 00:23:39.559
dollar, kind of inspired from Regex, so

00:23:38.030 --> 00:23:41.120
those make a little bit of sense. There's

00:23:39.559 --> 00:23:42.890
some other ones that, like, don't

00:23:41.120 --> 00:23:43.940
necessarily make way too much sense, but,

00:23:42.890 --> 00:23:46.310
there are only so many keys on your

00:23:43.940 --> 00:23:48.590
keyboard, so what are you going to do? For

00:23:46.310 --> 00:23:49.430
example, the "L" key moves your cursor to

00:23:48.590 --> 00:23:51.890
the lowest

00:23:49.430 --> 00:23:54.920
line that's shown on the screen. "L" for

00:23:51.890 --> 00:24:01.430
lowest makes sense, M for middle, and then H for

00:23:54.920 --> 00:24:02.660
highest, I guess. And, there's a whole

00:24:01.430 --> 00:24:04.250
bunch of other interesting movements

00:24:02.660 --> 00:24:05.330
like this. So, we're obviously not going

00:24:04.250 --> 00:24:07.070
to be able to cover all of them right

00:24:05.330 --> 00:24:08.690
now, but you'll be able to go through

00:24:07.070 --> 00:24:11.320
them in the Vim tutor exercise, which is

00:24:08.690 --> 00:24:15.790
exercise number one for this lecture.

00:24:11.320 --> 00:24:18.080
Some other ones I want to talk about now -

00:24:15.790 --> 00:24:19.640
maybe I'll talk about one more. There's

00:24:18.080 --> 00:24:21.440
another movement called "find". This is

00:24:19.640 --> 00:24:23.210
also kind of useful. Suppose I'm on this

00:24:21.440 --> 00:24:25.340
line, and I want to jump to the first

00:24:23.210 --> 00:24:27.260
character that equal's to... Like, I

00:24:25.340 --> 00:24:31.310
want to jump to the first "o". I can press

00:24:27.260 --> 00:24:33.860
"fo", and my cursor moves to the first

00:24:31.310 --> 00:24:35.210
"o". I've like, found "o". I can do fw and

00:24:33.860 --> 00:24:39.560
it'll move to the first "w", which I think

00:24:35.210 --> 00:24:40.880
is right here. fc: find the first C. I can

00:24:39.560 --> 00:24:44.510
also do the same thing, but backwards. If

00:24:40.880 --> 00:24:47.930
I do capital F, w, I can find the W that's

00:24:44.510 --> 00:24:49.760
before it. Capital F, s: find the s that's

00:24:47.930 --> 00:24:53.450
before that. And then, there's a variant

00:24:49.760 --> 00:24:56.690
of f, for find: t for to, so I can jump to

00:24:53.450 --> 00:24:58.520
O, and it jumps, like, until it's found o.

00:24:56.690 --> 00:25:03.110
But not on top of it, right before it. And

00:24:58.520 --> 00:25:04.820
capital T say, t, jumps backwards to the t

00:25:03.110 --> 00:25:07.190
except not all the way on top of it, one

00:25:04.820 --> 00:25:09.770
character before. And, so, you can already

00:25:07.190 --> 00:25:10.970
see that idea I talked about, of like, Vim

00:25:09.770 --> 00:25:13.160
is a programming language; you can, like,

00:25:10.970 --> 00:25:15.050
compose these commands. "F", and "T", are

00:25:13.160 --> 00:25:16.790
"find", and "to", and you can say "find" a

00:25:15.050 --> 00:25:20.180
particular character, or jump "to" a

00:25:16.790 --> 00:25:22.400
particular character. So, those are a

00:25:20.180 --> 00:25:26.660
couple of Vim movement commands. So, any

00:25:22.400 --> 00:25:32.050
questions about those so far? So this is -

00:25:26.660 --> 00:25:33.980
yeah, question? Or... no? Okay, cool. So,

00:25:32.050 --> 00:25:35.540
those are Vim movement commands.

00:25:33.980 --> 00:25:37.880
This is how you can navigate around a

00:25:35.540 --> 00:25:40.070
file quickly in normal mode. Now, another

00:25:37.880 --> 00:25:42.770
category of useful commands are editing

00:25:40.070 --> 00:25:44.480
commands. So, one we kind of already

00:25:42.770 --> 00:25:46.520
talked about is the "i" command

00:25:44.480 --> 00:25:48.500
for moving from "normal" mode to "insert"

00:25:46.520 --> 00:25:50.690
mode, where you can start just writing

00:25:48.500 --> 00:25:52.490
text. So, suppose I go up here and I press

00:25:50.690 --> 00:25:57.020
"i". Now I can type in whatever text I want

00:25:52.490 --> 00:25:58.370
"Hello world", "enter". Then, press

00:25:57.020 --> 00:26:00.890
"escape" to go back to normal mode, and

00:25:58.370 --> 00:26:01.640
I've made a change to my buffer. But,

00:26:00.890 --> 00:26:03.740
there are a whole bunch of other

00:26:01.640 --> 00:26:05.540
commands for making efficient edits

00:26:03.740 --> 00:26:07.760
that makes sense for when you're dealing

00:26:05.540 --> 00:26:09.410
with programming languages. So, one useful

00:26:07.760 --> 00:26:10.670
command that I accidentally used earlier,

00:26:09.410 --> 00:26:13.280
before teaching you about it, is the "o"

00:26:10.670 --> 00:26:16.130
command. So, suppose my cursor is, like,

00:26:13.280 --> 00:26:18.410
over here, and if I press "o", from normal

00:26:16.130 --> 00:26:19.490
mode, what it does, is it opens a new line

00:26:18.410 --> 00:26:22.040
below where my cursor is.

00:26:19.490 --> 00:26:23.420
That's what "o" stands for. And it, so it

00:26:22.040 --> 00:26:24.980
creates a new line, and it put me into

00:26:23.420 --> 00:26:27.290
insert mode. So, now I can start typing in

00:26:24.980 --> 00:26:29.600
some text, press escape, and go back to

00:26:27.290 --> 00:26:32.240
normal mode. And then, just like the "o"

00:26:29.600 --> 00:26:35.540
command, there's a capital "O" command, so

00:26:32.240 --> 00:26:37.850
if I'm here and I do capital "O", it puts

00:26:35.540 --> 00:26:41.690
me into insert mode above where I

00:26:37.850 --> 00:26:44.240
currently am. There's another Vim command

00:26:41.690 --> 00:26:47.690
for deleting things. So, suppose my cursor

00:26:44.240 --> 00:26:51.560
is, like, on top of this word right here,

00:26:47.690 --> 00:26:54.350
and I press the D key. "D" for delete. Oh,

00:26:51.560 --> 00:26:55.970
nothing happens; turns out that the D key

00:26:54.350 --> 00:26:57.860
needs to be combined with a movement

00:26:55.970 --> 00:26:59.630
command. So, remember we just talked about

00:26:57.860 --> 00:27:02.870
different movement commands, like hjkl,

00:26:59.630 --> 00:27:03.530
and, like, word, and backward word, and

00:27:02.870 --> 00:27:07.670
things like that.

00:27:03.530 --> 00:27:11.600
So, I press D. Whoops. I press D and I can

00:27:07.670 --> 00:27:13.970
press W, and it's deleted a word. So, let

00:27:11.600 --> 00:27:16.820
me undo that. Undoing in Vim is just u for

00:27:13.970 --> 00:27:19.940
undo. So, notice my cursor's right here. I

00:27:16.820 --> 00:27:21.770
do "dw": it's deleted a word. I can move

00:27:19.940 --> 00:27:25.100
around, and then delete another word.

00:27:21.770 --> 00:27:27.620
Suppose I'm - uh, keeps getting in the way

00:27:25.100 --> 00:27:29.420
Suppose I'm, like, somewhere in the middle

00:27:27.620 --> 00:27:31.130
of a word, and I want to delete to the end

00:27:29.420 --> 00:27:35.630
of a word. Any guesses for what

00:27:31.130 --> 00:27:39.320
combination of keys I'd use for that? "d"

00:27:35.630 --> 00:27:43.790
and what? de, exactly. Delete to the end of

00:27:39.320 --> 00:27:46.790
the word. Another useful editing command

00:27:43.790 --> 00:27:48.800
is the c command. c stands for change. So,

00:27:46.790 --> 00:27:50.840
change is really similar to delete,

00:27:48.800 --> 00:27:52.220
except change puts you in insert mode,

00:27:50.840 --> 00:27:54.500
because, like, I want to delete a thing,

00:27:52.220 --> 00:27:56.960
but change it to something else. So, if

00:27:54.500 --> 00:27:59.810
I'm here, and I do "ce", it's like, change

00:27:56.960 --> 00:28:00.950
to the end of the word. And, it gets rid

00:27:59.810 --> 00:28:02.630
of the contents until the end of the

00:28:00.950 --> 00:28:04.460
word, and notice it put me in insert mode.

00:28:02.630 --> 00:28:06.740
So now, whatever characters I type go

00:28:04.460 --> 00:28:11.270
into the buffer. If I press "escape", I go

00:28:06.740 --> 00:28:13.250
back into normal mode. And so, c and d are

00:28:11.270 --> 00:28:15.650
analogs: they both take motions as

00:28:13.250 --> 00:28:17.290
arguments. And, they will either delete

00:28:15.650 --> 00:28:20.950
that motion, or change

00:28:17.290 --> 00:28:24.370
that motion. So, for example, if you press

00:28:20.950 --> 00:28:25.990
the c key, there's also this pattern that,

00:28:24.370 --> 00:28:27.880
if you press a particular editing key

00:28:25.990 --> 00:28:30.400
twice, it'll have that effect on the

00:28:27.880 --> 00:28:32.980
given line. So, if I press "dd", that

00:28:30.400 --> 00:28:34.360
deletes the line. If I press "cc", that

00:28:32.980 --> 00:28:35.560
deletes the given line, but puts me in

00:28:34.360 --> 00:28:39.760
insert mode, so I can replace it with

00:28:35.560 --> 00:28:43.360
some other line. We'll cover a couple

00:28:39.760 --> 00:28:44.290
other, uh, editing commands, because then

00:28:43.360 --> 00:28:46.720
later we'll see how all these things

00:28:44.290 --> 00:28:48.700
interact together. So, another useful one

00:28:46.720 --> 00:28:50.290
is the x command. So, suppose my cursor is

00:28:48.700 --> 00:28:52.120
over some particular character. If I

00:28:50.290 --> 00:28:57.880
press "x", it just deletes that

00:28:52.120 --> 00:29:00.310
character. There's another command called

00:28:57.880 --> 00:29:02.260
r. If I'm over a particular character, and

00:29:00.310 --> 00:29:03.940
I press "r", it takes another character as

00:29:02.260 --> 00:29:05.440
an argument, and it replaces that

00:29:03.940 --> 00:29:12.550
particular character with some other

00:29:05.440 --> 00:29:14.110
character. And, I'll cover a couple more

00:29:12.550 --> 00:29:16.390
editing commands. So, I think one I

00:29:14.110 --> 00:29:17.980
talked about a moment ago - but, of course

00:29:16.390 --> 00:29:19.360
you can undo changes you've made in Vim.

00:29:17.980 --> 00:29:21.520
And the way you do that is by pressing

00:29:19.360 --> 00:29:23.230
"u" while you're in normal mode. So, u for

00:29:21.520 --> 00:29:24.850
undo is pretty easy to remember. So, I

00:29:23.230 --> 00:29:26.310
press "u" a whole bunch of times; it's

00:29:24.850 --> 00:29:28.750
undone all the changes I've made. And

00:29:26.310 --> 00:29:31.000
then, the opposite of undo is, of course,

00:29:28.750 --> 00:29:40.960
redo. And, the binding for that in Vim is

00:29:31.000 --> 00:29:42.310
control + R. All right, one other editing

00:29:40.960 --> 00:29:55.090
command I'm going to talk about is copy

00:29:42.310 --> 00:29:56.290
and paste because-oh yes, question? That's

00:29:55.090 --> 00:29:58.150
a - that's a great question! So, the

00:29:56.290 --> 00:29:59.500
question is, "Does 'undo' undo everything

00:29:58.150 --> 00:30:00.970
you've done since you've gone into

00:29:59.500 --> 00:30:02.380
insert mode, or just the last character?"

00:30:00.970 --> 00:30:03.280
It's - it's actually a little bit more

00:30:02.380 --> 00:30:05.860
complicated than that.

00:30:03.280 --> 00:30:07.540
"Undo" does, like, undoes the last change

00:30:05.860 --> 00:30:08.800
you've made. So, if you went into insert

00:30:07.540 --> 00:30:10.480
mode, and typed in some stuff, and went

00:30:08.800 --> 00:30:12.520
back into normal mode, and then press "u"

00:30:10.480 --> 00:30:14.560
for "undo", it'll undo all you've done in

00:30:12.520 --> 00:30:16.090
insert mode. But, if you've done some

00:30:14.560 --> 00:30:18.280
other type of editing command, like, say I

00:30:16.090 --> 00:30:20.140
press "x" to delete a character... If I do

00:30:18.280 --> 00:30:24.280
"u" for undo, it'll just undo that change

00:30:20.140 --> 00:30:26.440
that that editing command made. Now, does

00:30:24.280 --> 00:30:28.780
that answer the question? (Yeah) Great any

00:30:26.440 --> 00:30:32.780
other questions?

00:30:28.780 --> 00:30:35.480
Cool. So, I'll talk about copy and paste

00:30:32.780 --> 00:30:37.580
as well, because that's a popular one. The

00:30:35.480 --> 00:30:39.710
y command stands for copying, and the p

00:30:37.580 --> 00:30:41.810
command stands for pasting. y for "copy",

00:30:39.710 --> 00:30:43.370
because, yank. Like, that's the word they-

00:30:41.810 --> 00:30:46.310
that's the terminology that

00:30:43.370 --> 00:30:49.220
Vim uses for copying. And, these commands

00:30:46.310 --> 00:30:52.580
are- y also takes a motion as an argument.

00:30:49.220 --> 00:30:54.350
So if I do like, yy, it copies the current

00:30:52.580 --> 00:30:56.090
line. And, if I press "p" for "paste",

00:30:54.350 --> 00:30:57.260
notice that now these two lines are

00:30:56.090 --> 00:31:00.110
identical, because I've just pasted a

00:30:57.260 --> 00:31:02.330
line below. "u" for "undo". But if I do

00:31:00.110 --> 00:31:04.910
something like "yw", it's copied the word.

00:31:02.330 --> 00:31:05.450
And then I can do "p", and it just pasted

00:31:04.910 --> 00:31:08.930
that word again,

00:31:05.450 --> 00:31:10.700
right where my cursor was. One useful

00:31:08.930 --> 00:31:12.530
thing, especially in the context of copy

00:31:10.700 --> 00:31:14.150
and paste, is to be able to select a

00:31:12.530 --> 00:31:15.650
block of stuff and copy it, right? Like,

00:31:14.150 --> 00:31:16.940
this is probably how you used copy and

00:31:15.650 --> 00:31:19.220
paste in whatever editor you were using

00:31:16.940 --> 00:31:21.440
before. And so, that's where we get into

00:31:19.220 --> 00:31:23.210
the visual modes. So, these are another

00:31:21.440 --> 00:31:24.590
set of modes that are all related to

00:31:23.210 --> 00:31:26.030
each other, and that can be reached from

00:31:24.590 --> 00:31:28.790
normal mode, and they're used for

00:31:26.030 --> 00:31:31.040
selecting chunks of text. So, one mode is,

00:31:28.790 --> 00:31:33.140
just, regular visual mode. You can enter

00:31:31.040 --> 00:31:34.820
that by pressing v. And then, once you're

00:31:33.140 --> 00:31:36.650
in this mode, you can use most of the

00:31:34.820 --> 00:31:38.450
regular normal mode commands to move

00:31:36.650 --> 00:31:39.980
your pointer around. And it selects

00:31:38.450 --> 00:31:42.050
everything in between. So I can use, like,

00:31:39.980 --> 00:31:44.030
hjkl just to move the cursor, or I can

00:31:42.050 --> 00:31:45.890
use "w" to move by words, or different

00:31:44.030 --> 00:31:48.080
things like that, and it will select a

00:31:45.890 --> 00:31:49.490
block of text. And, once I've selected

00:31:48.080 --> 00:31:50.900
this block of text there are a whole bunch

00:31:49.490 --> 00:31:52.610
of different types of useful things you

00:31:50.900 --> 00:31:54.770
could do with it. One of the most popular

00:31:52.610 --> 00:31:57.320
things to do is copying this. So, once

00:31:54.770 --> 00:31:59.630
I've selected, I can do y to copy, and it

00:31:57.320 --> 00:32:01.280
puts me back into normal mode. And now,

00:31:59.630 --> 00:32:02.810
it's copied this to the - to the paste

00:32:01.280 --> 00:32:04.850
buffer. And then if I go somewhere else,

00:32:02.810 --> 00:32:07.670
and press "p", it pastes in that whole

00:32:04.850 --> 00:32:10.520
chunk of text I copied. And it's similar

00:32:07.670 --> 00:32:13.610
to visual mode, which selects kind of a

00:32:10.520 --> 00:32:15.560
contiguous stream of text. There's visual

00:32:13.610 --> 00:32:17.720
line mode: that can be reached by

00:32:15.560 --> 00:32:19.760
pressing capital V, and that selects

00:32:17.720 --> 00:32:21.470
whole lines at a time. And then there's

00:32:19.760 --> 00:32:23.150
VISUAL BLOCK mode, which can be selected

00:32:21.470 --> 00:32:24.890
by pressing "control" + " V", and that can

00:32:23.150 --> 00:32:26.240
select rectangular blocks of text. So

00:32:24.890 --> 00:32:31.670
this is something your old editor

00:32:26.240 --> 00:32:33.320
couldn't do. Alright, so, there's a lot

00:32:31.670 --> 00:32:35.120
more Vim editing commands to learn.

00:32:33.320 --> 00:32:36.710
There's lots of, like, really weird and

00:32:35.120 --> 00:32:38.420
fancy things. Like, for example, the tilde

00:32:36.710 --> 00:32:40.220
command changes the case of the

00:32:38.420 --> 00:32:41.690
character, or the selection that you've

00:32:40.220 --> 00:32:43.640
currently selected. So for example,

00:32:41.690 --> 00:32:45.620
I can take this, like, Visual Studio Code,

00:32:43.640 --> 00:32:48.260
and flip the case on the whole thing, by

00:32:45.620 --> 00:32:49.430
selecting it and pressing tilde. And,

00:32:48.260 --> 00:32:50.480
there's a whole bunch of other things

00:32:49.430 --> 00:32:52.160
like that; they get more and more

00:32:50.480 --> 00:32:54.050
esoteric as you go. So, we're not going to

00:32:52.160 --> 00:32:56.630
cover all of those, but you'll get to

00:32:54.050 --> 00:32:58.490
those in the exercises. So, those are Vim

00:32:56.630 --> 00:33:00.620
editing commands, and a lot of them can

00:32:58.490 --> 00:33:02.120
be composed with movement commands. So,

00:33:00.620 --> 00:33:09.260
any questions about either of those so

00:33:02.120 --> 00:33:12.680
far? Cool. So, moving along, another

00:33:09.260 --> 00:33:14.240
category of things -of commands- that are

00:33:12.680 --> 00:33:16.880
mostly relevant to normal mode are

00:33:14.240 --> 00:33:18.530
counts. So, you can give them a number, to

00:33:16.880 --> 00:33:22.100
do a particular thing, some number of

00:33:18.530 --> 00:33:25.430
times. So suppose my cursor is here, and I

00:33:22.100 --> 00:33:26.960
want to move down, like 1 2 3 4 lines. One

00:33:25.430 --> 00:33:29.390
way I can do that is by pressing "j" four

00:33:26.960 --> 00:33:32.570
times - go down four times. "kkkk" goes

00:33:29.390 --> 00:33:34.010
up four times. But, rather than pressing a

00:33:32.570 --> 00:33:37.430
particular key again, and again, I can use

00:33:34.010 --> 00:33:38.960
a count. So if I press "4", "j", it does j

00:33:37.430 --> 00:33:40.130
four times, right?

00:33:38.960 --> 00:33:42.290
Vim's interface is a programming

00:33:40.130 --> 00:33:45.890
language. If I do "4k", it moves up four

00:33:42.290 --> 00:33:47.600
times. If I am here, and I press "v" to go

00:33:45.890 --> 00:33:49.040
into visual mode... Okay so now I can move

00:33:47.600 --> 00:33:51.680
my cursor around, and select blocks of

00:33:49.040 --> 00:33:53.660
text. I can do, like, "eee" to select a

00:33:51.680 --> 00:33:56.600
couple of words, but, I could also go back

00:33:53.660 --> 00:33:59.720
here -v for visual mode- and press three e

00:33:56.600 --> 00:34:03.080
to select, like, three "ends of words"

00:33:59.720 --> 00:34:05.060
forward. And then of course these can also

00:34:03.080 --> 00:34:08.000
be combined with editing commands. So,

00:34:05.060 --> 00:34:10.910
like, suppose I want to delete seven

00:34:08.000 --> 00:34:13.970
words. I can do that by moving my cursor

00:34:10.910 --> 00:34:17.660
somewhere, and doing "7dw". Seven delete

00:34:13.970 --> 00:34:19.490
words. And so, this is particularly useful

00:34:17.660 --> 00:34:21.260
for things like, suppose my cursor is

00:34:19.490 --> 00:34:22.460
somewhere on the screen, and I'm looking

00:34:21.260 --> 00:34:24.020
somewhere else on the screen, or, I want

00:34:22.460 --> 00:34:26.240
my cursor to go to that particular line.

00:34:24.020 --> 00:34:28.400
Notice that I've set up relative line

00:34:26.240 --> 00:34:29.750
numbering on the left. So, wherever my

00:34:28.400 --> 00:34:31.580
cursor is, it shows the current line

00:34:29.750 --> 00:34:33.830
number, but everywhere else, it's just the

00:34:31.580 --> 00:34:35.870
offset from where I am. Now, suppose my

00:34:33.830 --> 00:34:38.480
cursor is here, but I want to move down

00:34:35.870 --> 00:34:40.160
to the like "Microsoft Word" down here, so

00:34:38.480 --> 00:34:41.810
that's eight lines down. So, what

00:34:40.160 --> 00:34:44.020
combination of keys would I press, to do

00:34:41.810 --> 00:34:45.560
that? Like, what's the most efficient way?

00:34:44.020 --> 00:34:47.810
Yeah, exactly!

00:34:45.560 --> 00:34:50.440
Let's try that out-8j-and my cursor moved

00:34:47.810 --> 00:34:50.440
down to this line.

00:34:51.270 --> 00:34:57.880
Okay. And then, one, final category of key

00:34:56.110 --> 00:34:59.920
meanings in Vim is something called

00:34:57.880 --> 00:35:02.200
modifiers. So we have, so far, movement,

00:34:59.920 --> 00:35:04.900
edits, counts, and, finally, we have

00:35:02.200 --> 00:35:06.520
modifiers. So, modifiers kind of change

00:35:04.900 --> 00:35:08.830
the meaning of a movement command a

00:35:06.520 --> 00:35:11.530
little bit. And, a couple modifiers that

00:35:08.830 --> 00:35:15.190
are especially useful are the "a" and "i"

00:35:11.530 --> 00:35:18.010
modifier. So, a stands for like around and

00:35:15.190 --> 00:35:19.900
"i" stands for inside. And, to see where

00:35:18.010 --> 00:35:21.760
this is really useful, I can move my

00:35:19.900 --> 00:35:22.480
cursor to somewhere like here, for

00:35:21.760 --> 00:35:24.670
example.

00:35:22.480 --> 00:35:26.320
So, hopefully, most of you are familiar

00:35:24.670 --> 00:35:28.240
with markdown syntax - and if not it

00:35:26.320 --> 00:35:30.490
doesn't matter too much. Uh, this is a

00:35:28.240 --> 00:35:31.780
link in markdown; it's a text rendered in

00:35:30.490 --> 00:35:33.610
square brackets, and then the link in

00:35:31.780 --> 00:35:35.500
parentheses. Suppose my cursor is inside

00:35:33.610 --> 00:35:38.350
here, and I want to change the text

00:35:35.500 --> 00:35:40.150
corresponding to this link. Well, one way

00:35:38.350 --> 00:35:43.480
I could do that is, like, move back here

00:35:40.150 --> 00:35:45.130
with b, and, like, 2dw, and then "i" to go

00:35:43.480 --> 00:35:46.450
into insert mode. That's one of the

00:35:45.130 --> 00:35:47.950
many ways I can make this change, and I

00:35:46.450 --> 00:35:51.070
can type in whatever other thing I want -

00:35:47.950 --> 00:35:53.410
u to undo, u to undo. Another way I could

00:35:51.070 --> 00:35:58.030
have done that is change two words - "c2w"

00:35:53.410 --> 00:35:59.950
- and then type in some other text. But,

00:35:58.030 --> 00:36:03.280
one final way I could do the same change

00:35:59.950 --> 00:36:05.380
is using the modifier commands to talk

00:36:03.280 --> 00:36:07.120
about how I want to interact with these

00:36:05.380 --> 00:36:09.490
different types of grouping things like

00:36:07.120 --> 00:36:12.070
parentheses and square brackets. So, one

00:36:09.490 --> 00:36:15.610
final way of doing this is change inside

00:36:12.070 --> 00:36:17.440
square brackets-"c" "i" "["-and that puts

00:36:15.610 --> 00:36:20.230
me into insert mode, after deleting the

00:36:17.440 --> 00:36:21.400
contents that are inside the brackets. So,

00:36:20.230 --> 00:36:22.690
do you see how we can take all these

00:36:21.400 --> 00:36:24.310
different ingredients, like we talked

00:36:22.690 --> 00:36:25.570
about "change", and we could combine that

00:36:24.310 --> 00:36:27.460
with different movement commands. We

00:36:25.570 --> 00:36:30.100
talked about inside, how it's a modifier.

00:36:27.460 --> 00:36:32.770
And then we talked about, uh... we didn't

00:36:30.100 --> 00:36:34.230
talk about parentheses. But, if your

00:36:32.770 --> 00:36:36.070
cursor is hovering over a different, uh,

00:36:34.230 --> 00:36:37.810
different types of grouping things like

00:36:36.070 --> 00:36:39.880
parentheses, or square brackets, you can

00:36:37.810 --> 00:36:40.990
press the percent movement key to jump

00:36:39.880 --> 00:36:45.340
back and forth between matching

00:36:40.990 --> 00:36:49.510
parentheses. If I go over here and I do d,

00:36:45.340 --> 00:36:52.480
i, (, I can delete the contents

00:36:49.510 --> 00:36:55.780
inside these parentheses. And so, those

00:36:52.480 --> 00:36:57.550
are Vim, uh, modifiers. I guess we talked

00:36:55.780 --> 00:37:00.310
about i, but we didn't talk about a. If I

00:36:57.550 --> 00:37:02.080
do "da(", it deletes a whole,

00:37:00.310 --> 00:37:04.460
like parenthesized group including the

00:37:02.080 --> 00:37:10.730
parentheses so I is inside

00:37:04.460 --> 00:37:11.839
is around or including all right so

00:37:10.730 --> 00:37:13.670
those are basically the different

00:37:11.839 --> 00:37:15.890
categories of things you can combine

00:37:13.670 --> 00:37:18.050
together, when interacting with Vim's

00:37:15.890 --> 00:37:20.330
interface. So, any questions about that or

00:37:18.050 --> 00:37:28.820
the overall idea of this interface being

00:37:20.330 --> 00:37:31.580
a programming language? Cool. So, let's do

00:37:28.820 --> 00:37:33.859
a quick demo, to kind of demonstrate the

00:37:31.580 --> 00:37:36.290
power of this editor. And, it will kind of

00:37:33.859 --> 00:37:38.240
help us see how this tool can work

00:37:36.290 --> 00:37:41.260
really fast and kind of match the speed

00:37:38.240 --> 00:37:43.760
at which we think. So, over here is a very

00:37:41.260 --> 00:37:44.780
broken "fizzbuzz" implementation that

00:37:43.760 --> 00:37:46.640
doesn't actually print anything.

00:37:44.780 --> 00:37:48.680
Uh, hopefully, most of you have heard of

00:37:46.640 --> 00:37:51.080
"fizzbuzz" - if not, I'll explain it super

00:37:48.680 --> 00:37:52.730
briefly. Uh, "fizzbuzz" is a programming

00:37:51.080 --> 00:37:54.290
exercise where you print the numbers 1

00:37:52.730 --> 00:37:56.540
through n, but when the number is

00:37:54.290 --> 00:37:58.700
divisible by 3, you print fizz - when it's

00:37:56.540 --> 00:38:00.859
divisible by 5, you print buzz. And, when

00:37:58.700 --> 00:38:02.839
it's divisible by both 3, and 5. you print

00:38:00.859 --> 00:38:05.089
fizzbuzz. And, if none of those apply, you

00:38:02.839 --> 00:38:09.290
just print the number. So, you should

00:38:05.089 --> 00:38:13.460
print like 1, 2, fizz, 4, buzz, and so on.

00:38:09.290 --> 00:38:16.550
But, if I run this program, it doesn't

00:38:13.460 --> 00:38:20.089
print anything here I have them on the

00:38:16.550 --> 00:38:21.530
left in just a terminal on the right ok

00:38:20.089 --> 00:38:23.750
so there's a bunch of issues with this

00:38:21.530 --> 00:38:26.470
one is that main is never called so

00:38:23.750 --> 00:38:29.450
let's start off with fixing that so

00:38:26.470 --> 00:38:31.960
here's how I would make this change and

00:38:29.450 --> 00:38:34.250
notice how few keystrokes this requires

00:38:31.960 --> 00:38:37.609
capital G means go to the bottom of the

00:38:34.250 --> 00:38:39.650
file o opens a new line below and now I

00:38:37.609 --> 00:38:45.380
can just type in stuff so I'm an insert

00:38:39.650 --> 00:38:47.210
mode okay so I've typed in whatever

00:38:45.380 --> 00:38:50.480
change I want to make escape to go back

00:38:47.210 --> 00:38:53.540
to normal mode if I do : W so command

00:38:50.480 --> 00:38:54.650
mode right let me go back here okay now

00:38:53.540 --> 00:38:56.690
at least my program prints something

00:38:54.650 --> 00:38:58.940
when I run it another issue with this

00:38:56.690 --> 00:39:02.750
program is that it starts at 0 instead

00:38:58.940 --> 00:39:05.030
of 1 so let's go fix that so I want to

00:39:02.750 --> 00:39:06.950
go over to this range whoops this range

00:39:05.030 --> 00:39:08.480
thing and it shouldn't be going from 0

00:39:06.950 --> 00:39:11.270
to limit it should be going from 1 to

00:39:08.480 --> 00:39:12.650
limit plus 1 1 command which I didn't

00:39:11.270 --> 00:39:16.060
show you about is how you search in vim

00:39:12.650 --> 00:39:16.060
so you press forward slash

00:39:17.010 --> 00:39:21.930
to close this and restart it if you

00:39:19.080 --> 00:39:24.840
press forward slash it starts search so

00:39:21.930 --> 00:39:26.220
if I type in range enter my cursor goes

00:39:24.840 --> 00:39:27.810
from wherever it was before to the first

00:39:26.220 --> 00:39:28.920
instance of range it found so it's a

00:39:27.810 --> 00:39:31.680
really efficient way of moving where I

00:39:28.920 --> 00:39:33.990
want to move WW to move forward two

00:39:31.680 --> 00:39:36.330
words I to go into insert mode add the

00:39:33.990 --> 00:39:38.310
one comma space escape I'm back in

00:39:36.330 --> 00:39:40.080
normal mode this is a very common

00:39:38.310 --> 00:39:41.850
pattern in vim you stay in normal mode

00:39:40.080 --> 00:39:43.260
you go somewhere you go into insert mode

00:39:41.850 --> 00:39:44.880
you make a tiny change and you jump

00:39:43.260 --> 00:39:45.900
right back to normal mode like normal

00:39:44.880 --> 00:39:48.810
mode is home and that's where you should

00:39:45.900 --> 00:39:51.030
be most of the time I also want to add a

00:39:48.810 --> 00:39:55.430
plus one so e to go to the end of this

00:39:51.030 --> 00:39:58.140
word a for a pend plus one escape

00:39:55.430 --> 00:40:00.810
alright fix that problem and other issue

00:39:58.140 --> 00:40:02.940
is that this program prints fizz for

00:40:00.810 --> 00:40:05.970
both divisible by three and five so

00:40:02.940 --> 00:40:07.920
let's fix that slash fizz searches for

00:40:05.970 --> 00:40:11.790
fizz been oppressed and it goes to the

00:40:07.920 --> 00:40:13.710
next match see I press E I quote changes

00:40:11.790 --> 00:40:15.660
what's inside the quote so it's deleted

00:40:13.710 --> 00:40:17.460
the fizz and put me in insert mode right

00:40:15.660 --> 00:40:18.510
in between those two quotes and I can

00:40:17.460 --> 00:40:23.460
type in whatever I want

00:40:18.510 --> 00:40:26.630
escape to go back to normal mode so

00:40:23.460 --> 00:40:28.890
great I've fixed that particular problem

00:40:26.630 --> 00:40:31.710
another problem with this program is

00:40:28.890 --> 00:40:37.710
that it prints fizz and Buzz on separate

00:40:31.710 --> 00:40:42.150
lines for multiples of 15 so let's let's

00:40:37.710 --> 00:40:42.870
go and fix that let me go down to this

00:40:42.150 --> 00:40:44.580
line here

00:40:42.870 --> 00:40:46.350
one way I can don't actually worry about

00:40:44.580 --> 00:40:47.430
like the actual contents of this program

00:40:46.350 --> 00:40:48.690
like this some stupid program that

00:40:47.430 --> 00:40:51.000
doesn't matter pay attention to what

00:40:48.690 --> 00:40:52.170
keys I'm pressing in vim that allow me

00:40:51.000 --> 00:40:54.960
to make changes to this program really

00:40:52.170 --> 00:40:56.790
efficiently so my cursor is on this line

00:40:54.960 --> 00:40:59.460
i press dollar to go to the end of this

00:40:56.790 --> 00:41:01.170
line i for insert mode okay and i'm

00:40:59.460 --> 00:41:03.330
typing some stuff escape to go back to

00:41:01.170 --> 00:41:07.050
normal mode now I want to make the same

00:41:03.330 --> 00:41:11.610
change the print below look at this JJ

00:41:07.050 --> 00:41:13.260
dot so what dot dozen vim is it repeats

00:41:11.610 --> 00:41:15.990
the previous editing command that was

00:41:13.260 --> 00:41:17.880
made and so this is a really nice way of

00:41:15.990 --> 00:41:19.890
doing repetitive tasks without typing

00:41:17.880 --> 00:41:21.630
the same thing over and over again so in

00:41:19.890 --> 00:41:24.630
that particular case that inserted comma

00:41:21.630 --> 00:41:27.110
end quote and so it applied the same

00:41:24.630 --> 00:41:29.580
thing on this line when I press dot and

00:41:27.110 --> 00:41:30.690
then when I guess one final part of this

00:41:29.580 --> 00:41:32.930
demo is

00:41:30.690 --> 00:41:34.620
we will fix the issue that this program

00:41:32.930 --> 00:41:35.670
maybe should take a command-line

00:41:34.620 --> 00:41:38.520
argument instead of having this

00:41:35.670 --> 00:41:40.440
hard-coded 10 down here so how do we do

00:41:38.520 --> 00:41:43.170
that I'll press GG to go to the top

00:41:40.440 --> 00:41:44.490
capital o so now I've opened a line

00:41:43.170 --> 00:41:47.220
above and I'm going to type in some text

00:41:44.490 --> 00:41:49.710
like imports this enter escape to go

00:41:47.220 --> 00:41:52.110
back to normal mode and then I want to

00:41:49.710 --> 00:41:54.870
go down to where this 10 is so slash 10

00:41:52.110 --> 00:41:57.540
makes me jump straight down there CI

00:41:54.870 --> 00:41:59.760
pren to edit what's inside the

00:41:57.540 --> 00:42:02.150
parentheses and now I can type in like

00:41:59.760 --> 00:42:07.080
whatever thing I need to type in here

00:42:02.150 --> 00:42:09.840
and then once I've done this my program

00:42:07.080 --> 00:42:10.920
does fizzbuzz correctly I think I missed

00:42:09.840 --> 00:42:12.390
one change I wanted to make but it

00:42:10.920 --> 00:42:14.540
doesn't matter this demonstrates that

00:42:12.390 --> 00:42:17.250
you can make lots of changes really fast

00:42:14.540 --> 00:42:23.400
so any questions about this demo or the

00:42:17.250 --> 00:42:27.960
overall idea we've been talking about ok

00:42:23.400 --> 00:42:29.550
so this will be covered Tuesday so the

00:42:27.960 --> 00:42:31.710
kind of outside environment I'm running

00:42:29.550 --> 00:42:33.630
vim on the left and my shell on the

00:42:31.710 --> 00:42:38.910
right and then this is team ox on the

00:42:33.630 --> 00:42:39.900
outside one variant of that question

00:42:38.910 --> 00:42:41.670
might be like how do you switch between

00:42:39.900 --> 00:42:42.840
different vim windows and you can see

00:42:41.670 --> 00:42:44.250
the lecture notes for that but there's a

00:42:42.840 --> 00:42:45.720
key binding for that so if you have the

00:42:44.250 --> 00:42:50.240
same window open or multiple things open

00:42:45.720 --> 00:42:50.240
there's a way of doing that question ah

00:42:50.840 --> 00:42:56.520
good question so delete takes a motion

00:42:54.570 --> 00:42:58.110
and then removes those contents but

00:42:56.520 --> 00:43:00.120
keeps you in normal mode so you can keep

00:42:58.110 --> 00:43:02.430
just moving around in a file what change

00:43:00.120 --> 00:43:03.900
does is very similar to delete it takes

00:43:02.430 --> 00:43:06.150
motions and treats them in the same way

00:43:03.900 --> 00:43:07.980
deletes those contents but then puts you

00:43:06.150 --> 00:43:11.280
in insert mode and so it saves you from

00:43:07.980 --> 00:43:13.290
typing one extra keystroke so if I'm

00:43:11.280 --> 00:43:16.380
here for example I want to delete main

00:43:13.290 --> 00:43:18.240
DW deletes a word but now if I press

00:43:16.380 --> 00:43:21.720
whatever key likes I press J it just

00:43:18.240 --> 00:43:23.490
moved me down if I undo that do cw4

00:43:21.720 --> 00:43:24.810
change a word now it's actually put me

00:43:23.490 --> 00:43:28.640
into insert mode and I can type in

00:43:24.810 --> 00:43:31.890
whatever I want it to insert so DWI is

00:43:28.640 --> 00:43:33.810
the same thing as CW but it saves a

00:43:31.890 --> 00:43:35.280
keystroke one thing we've linked in the

00:43:33.810 --> 00:43:37.140
resources is something called vim golf

00:43:35.280 --> 00:43:39.840
basically people have set up a game

00:43:37.140 --> 00:43:41.400
online where you can get an editing task

00:43:39.840 --> 00:43:43.590
and try to figure out the minimal number

00:43:41.400 --> 00:43:44.490
of keystrokes necessary to complete that

00:43:43.590 --> 00:43:46.020
editing

00:43:44.490 --> 00:43:47.340
it's actually really addictive so I'd

00:43:46.020 --> 00:43:52.680
only suggest going on their chest and

00:43:47.340 --> 00:44:00.450
script time I think I saw a hand for

00:43:52.680 --> 00:44:02.070
another question yeah uh period yeah one

00:44:00.450 --> 00:44:05.750
of the most useful of em commands good

00:44:02.070 --> 00:44:05.750
question any other questions

00:44:06.740 --> 00:44:13.260
cool so I think we have about five

00:44:10.800 --> 00:44:14.760
minutes left and I'm gonna briefly talk

00:44:13.260 --> 00:44:15.990
about a thing that's also covered in

00:44:14.760 --> 00:44:19.470
detail in the notes so make sure you

00:44:15.990 --> 00:44:22.349
look at the notes for this so vim is a

00:44:19.470 --> 00:44:24.420
programmers text editor and so of course

00:44:22.349 --> 00:44:25.740
it's highly programmable not only

00:44:24.420 --> 00:44:27.720
through its interface that's a

00:44:25.740 --> 00:44:29.099
programming language but also a couple

00:44:27.720 --> 00:44:31.050
of different ways there's lots of

00:44:29.099 --> 00:44:32.970
settings that you can tweak to match

00:44:31.050 --> 00:44:34.740
your preferences and you can also

00:44:32.970 --> 00:44:37.590
install plugins for them that do all

00:44:34.740 --> 00:44:40.380
sorts of useful stuff so the way vim is

00:44:37.590 --> 00:44:42.930
configured is through a file on disk

00:44:40.380 --> 00:44:45.480
called vim RC and you'll see this is a

00:44:42.930 --> 00:44:47.340
common pattern in a lot of shell based

00:44:45.480 --> 00:44:49.349
tools there'll be a plain text file that

00:44:47.340 --> 00:44:50.880
configures how the Tool Works and so if

00:44:49.349 --> 00:44:53.670
I edit this file and it may or may not

00:44:50.880 --> 00:44:56.310
exist on your machine yet but I've

00:44:53.670 --> 00:44:58.170
downloaded the we've created a kind of

00:44:56.310 --> 00:44:59.430
default vim RC for you and linked it on

00:44:58.170 --> 00:45:02.190
the course website so you can start with

00:44:59.430 --> 00:45:04.859
that one if I do vim tilde slash boom RC

00:45:02.190 --> 00:45:07.080
I can see here a bunch of comments and

00:45:04.859 --> 00:45:09.060
then particular commands like by default

00:45:07.080 --> 00:45:11.280
we want syntax highlighting on and we

00:45:09.060 --> 00:45:12.750
want line numbers if we didn't do some

00:45:11.280 --> 00:45:14.880
of these things like let me remove the

00:45:12.750 --> 00:45:16.500
stuff that sets line numbers if I remove

00:45:14.880 --> 00:45:17.790
those configurations and relaunch vim

00:45:16.500 --> 00:45:21.270
notice that I no longer have line

00:45:17.790 --> 00:45:23.099
numbers on the left but yeah so in short

00:45:21.270 --> 00:45:26.099
there's a lot of stuff you can configure

00:45:23.099 --> 00:45:28.589
with them we've given you a very basic

00:45:26.099 --> 00:45:29.880
configuration that tries to like remove

00:45:28.589 --> 00:45:32.160
some of the kind of weird behavior

00:45:29.880 --> 00:45:33.480
that's on by default in vim but we don't

00:45:32.160 --> 00:45:35.550
really try to enforce too many of our

00:45:33.480 --> 00:45:37.080
other opinions on you but of course like

00:45:35.550 --> 00:45:39.210
the three of us used them a lot and we

00:45:37.080 --> 00:45:41.310
have heavily customized VMR C's so we've

00:45:39.210 --> 00:45:42.480
linked to our personal configurations

00:45:41.310 --> 00:45:44.550
too if you want to take anything from

00:45:42.480 --> 00:45:46.050
that and also like thousands or like

00:45:44.550 --> 00:45:47.640
millions of people share their var C's

00:45:46.050 --> 00:45:48.450
on github so there's lots of places to

00:45:47.640 --> 00:45:49.920
look for inspiration

00:45:48.450 --> 00:45:53.040
there's also cool blog posts on this

00:45:49.920 --> 00:45:54.810
topic another thing you can do in vim is

00:45:53.040 --> 00:45:56.820
you can extend it with plugins that do

00:45:54.810 --> 00:45:58.080
all sorts of useful things this lets you

00:45:56.820 --> 00:45:59.730
do things like fuzzy file

00:45:58.080 --> 00:46:00.960
finding which a lot of text editors come

00:45:59.730 --> 00:46:02.790
with by default so you can get like a

00:46:00.960 --> 00:46:04.710
pop-up window you can type in a name of

00:46:02.790 --> 00:46:07.020
a file or approximately the name of a

00:46:04.710 --> 00:46:08.480
file and find it very quickly or there

00:46:07.020 --> 00:46:10.920
are things that show you like

00:46:08.480 --> 00:46:14.970
visualizations of undo history there are

00:46:10.920 --> 00:46:16.350
things that show you like file explorers

00:46:14.970 --> 00:46:18.360
things like that so we've linked to a

00:46:16.350 --> 00:46:20.520
couple of our favorite plugins on the

00:46:18.360 --> 00:46:22.230
course website and so I highly recommend

00:46:20.520 --> 00:46:23.340
becoming familiar with how to install a

00:46:22.230 --> 00:46:24.840
plug-in because it takes like three

00:46:23.340 --> 00:46:29.580
seconds and some of them are really cool

00:46:24.840 --> 00:46:32.130
and then finally the last topic I'll

00:46:29.580 --> 00:46:34.680
briefly mention before we finish today's

00:46:32.130 --> 00:46:37.170
lecture is vim mode and other programs

00:46:34.680 --> 00:46:38.760
so turns out that a lot of programmers

00:46:37.170 --> 00:46:40.650
we're really excited about VIMS

00:46:38.760 --> 00:46:42.780
interface and so they've implemented

00:46:40.650 --> 00:46:44.730
similar functionality and other tools

00:46:42.780 --> 00:46:47.730
for example like I've configured my

00:46:44.730 --> 00:46:49.530
Python repple to run in vim mode so I

00:46:47.730 --> 00:46:51.720
can like type in stuff here and if I

00:46:49.530 --> 00:46:53.250
press escape now I'm in normal mode in

00:46:51.720 --> 00:46:55.230
my Python repple and I can like move

00:46:53.250 --> 00:46:58.190
back and forth and like press X here

00:46:55.230 --> 00:47:01.530
delete a thing like CW change a word and

00:46:58.190 --> 00:47:03.210
do all those good things and it's not

00:47:01.530 --> 00:47:05.910
just the Python repple like I have my

00:47:03.210 --> 00:47:07.890
terminal behaving this way too so like I

00:47:05.910 --> 00:47:10.050
can type in whatever I want here and

00:47:07.890 --> 00:47:11.430
like escape and I'm in normal mode I can

00:47:10.050 --> 00:47:13.320
go here and like go into visual mode

00:47:11.430 --> 00:47:15.570
inside my terminal and like select

00:47:13.320 --> 00:47:19.680
blocks of text press tilde to change the

00:47:15.570 --> 00:47:22.080
case whatever so we've linked sir like

00:47:19.680 --> 00:47:25.800
how exactly you can enable vim mode for

00:47:22.080 --> 00:47:27.510
like bash z shell fish a lot of read

00:47:25.800 --> 00:47:28.710
line based programs like jupiter

00:47:27.510 --> 00:47:30.330
notebook a whole bunch of other things

00:47:28.710 --> 00:47:32.130
and if it's not another place you can

00:47:30.330 --> 00:47:33.840
probably find it by googling it because

00:47:32.130 --> 00:47:36.030
a lot of people like to have this sort

00:47:33.840 --> 00:47:37.380
of functionality and if you're really

00:47:36.030 --> 00:47:39.270
gonna like commit to learning them I

00:47:37.380 --> 00:47:41.490
think it's valuable to enable this sort

00:47:39.270 --> 00:47:43.080
of like vim emulation mode in every tool

00:47:41.490 --> 00:47:44.970
you use is like one or like make you

00:47:43.080 --> 00:47:46.800
learn the tool a lot better and to once

00:47:44.970 --> 00:47:47.970
you become good at vim like those skills

00:47:46.800 --> 00:47:53.130
will now transfer to all your other

00:47:47.970 --> 00:47:54.840
tools you use okay so I think that's it

00:47:53.130 --> 00:47:57.060
for our rapid introduction to them

00:47:54.840 --> 00:47:58.320
there's some other neat material that we

00:47:57.060 --> 00:47:59.790
weren't able to fit in today's lecture

00:47:58.320 --> 00:48:01.140
but it's in the lecture notes and then

00:47:59.790 --> 00:48:02.880
finally I highly recommend going through

00:48:01.140 --> 00:48:05.220
the exercises for today like at least

00:48:02.880 --> 00:48:07.440
for me personally I think spending time

00:48:05.220 --> 00:48:08.910
learning my text editor has been like

00:48:07.440 --> 00:48:10.140
the most beneficial thing out of like

00:48:08.910 --> 00:48:11.580
the kinds of things we're teaching in

00:48:10.140 --> 00:48:14.020
this class

00:48:11.580 --> 00:48:15.540
so yeah that's it for today's lecture

00:48:14.020 --> 00:48:17.530
and we'll see you tomorrow

00:48:15.540 --> 00:48:20.320
note that we've changed tomorrow's

00:48:17.530 --> 00:48:22.060
lecture to data wrangling Thursday and

00:48:20.320 --> 00:48:23.500
Tuesday lectures are now switched this

00:48:22.060 --> 00:48:25.000
is reflected on the course website in

00:48:23.500 --> 00:48:27.510
case anybody was going to come to one

00:48:25.000 --> 00:48:27.510
but not the other