0:00:00.030,0:00:05.339 okay bene benvenuti alla terza lezione 0:00:03.360,0:00:07.500 del semestre mancante 0:00:05.339,0:00:09.990 di CI oggi parleremo 0:00:07.500,0:00:11.759 di text editors questo è uno 0:00:09.990,0:00:13.259 argomento che mi piace molto e penso che sia 0:00:11.759,0:00:14.940 uno dei argomenti più importanti che 0:00:13.259,0:00:17.130 insegneremo in questa classe perché come 0:00:14.940,0:00:19.619 programmatori spenderete molto del vostro tempo 0:00:17.130,0:00:21.840 a modificare testi e programmi 0:00:19.619,0:00:23.609 se investe tempo nel rendervi 0:00:21.840,0:00:25.580 più efficienti nel farlo, risparmierete 0:00:23.609,0:00:27.990 un sacco di tempo probabilmente centinaia di ore 0:00:25.580,0:00:31.980 durante il corso della vostra laurea o 0:00:27.990,0:00:33.510 durante la vostra cariera lavorativa, 0:00:31.980,0:00:36.480 i text editors sono leggermente differenti da 0:00:33.510,0:00:38.280 altri programmi che potresti usare per modificare ad esempio 0:00:36.480,0:00:39.750 cose come la prosa Inglese perchè 0:00:38.280,0:00:41.760 i programmare è differente dal scrivere 0:00:39.750,0:00:44.160 una prosa Inglese, quando programmate 0:00:41.760,0:00:45.600 spendete molto tempo nel leggere cosa 0:00:44.160,0:00:47.579 avevate scritto, spendete molto tempo 0:00:45.600,0:00:49.079 navigating around a buffer and you spend 0:00:47.579,0:00:51.030 a lot of time making little edits to 0:00:49.079,0:00:52.860 code all over the place rather than just 0:00:51.030,0:00:53.789 writing in a long stream like you do 0:00:52.860,0:00:55.289 when you're writing an essay or 0:00:53.789,0:00:56.460 something and so it makes sense that 0:00:55.289,0:00:57.899 there different programs for these 0:00:56.460,0:00:59.309 different purposes right so yeah things 0:00:57.899,0:01:01.440 like Microsoft Word for writing essays 0:00:59.309,0:01:05.820 and things like vim and Emacs and vs 0:01:01.440,0:01:07.409 code and sublime for writing code so the 0:01:05.820,0:01:09.180 way you learn a text editor and become 0:01:07.409,0:01:11.130 really good at it is you start with a 0:01:09.180,0:01:12.840 tutorial and so that's basically going 0:01:11.130,0:01:15.720 to be the function of today's lecture 0:01:12.840,0:01:17.759 plus the exercises we've given you and 0:01:15.720,0:01:19.950 then after the tutorial you need to 0:01:17.759,0:01:22.020 stick with the editor for all your 0:01:19.950,0:01:24.000 editing tasks and when you're learning a 0:01:22.020,0:01:25.380 sophisticated tool so today we're going 0:01:24.000,0:01:26.850 to teach you vim which is one powerful 0:01:25.380,0:01:28.229 editor that a lot of programmers use 0:01:26.850,0:01:30.240 when you're learning such a 0:01:28.229,0:01:32.400 sophisticated tool it may be the case 0:01:30.240,0:01:33.750 that initially switching to this tool 0:01:32.400,0:01:35.850 slows you down a little bit when you're 0:01:33.750,0:01:38.729 programming but stick with it because 0:01:35.850,0:01:41.340 I'd say that in about 20 hours of 0:01:38.729,0:01:42.990 programming using a new editor you'll be 0:01:41.340,0:01:44.790 back to the same speed at which you 0:01:42.990,0:01:46.350 programmed using your old tool and then 0:01:44.790,0:01:47.759 after that the benefits will start and 0:01:46.350,0:01:50.189 you'll get faster and faster as you 0:01:47.759,0:01:53.579 learn more with these sophisticated 0:01:50.189,0:01:55.079 programs like them it takes not way too 0:01:53.579,0:01:58.200 long to learn the basics but a lifetime 0:01:55.079,0:01:59.759 to master and so throughout the time 0:01:58.200,0:02:01.649 you're using this tool make sure you 0:01:59.759,0:02:03.240 look things up as you go if you ever get 0:02:01.649,0:02:04.710 to a point where you're like oh this is 0:02:03.240,0:02:06.420 a really inefficient way of doing things 0:02:04.710,0:02:09.660 is there a better way the answer is 0:02:06.420,0:02:11.730 almost always yes because these text 0:02:09.660,0:02:13.709 editors were written by programmers for 0:02:11.730,0:02:13.970 programmers and so of course like the 0:02:13.709,0:02:15.200 peep 0:02:13.970,0:02:17.330 I wrote these tolls ran into the same 0:02:15.200,0:02:18.080 kinds of issues and fixed them so that 0:02:17.330,0:02:19.760 you don't need to deal with these 0:02:18.080,0:02:21.860 anymore and so yeah as you're learning 0:02:19.760,0:02:23.870 make sure you look things up as you go 0:02:21.860,0:02:25.370 either use Google or feel free to send 0:02:23.870,0:02:27.320 us emails if you have questions or come 0:02:25.370,0:02:29.590 to office hours and we'll help you 0:02:27.320,0:02:32.300 figure out how to do things really fast 0:02:29.590,0:02:34.130 so as far as which editor to learn in 0:02:32.300,0:02:35.510 previous iterations of this class we 0:02:34.130,0:02:36.890 actually avoided teaching a specific 0:02:35.510,0:02:39.050 editor because we didn't want to enforce 0:02:36.890,0:02:40.430 our opinions on you guys but we actually 0:02:39.050,0:02:42.050 think that it's really useful to teach 0:02:40.430,0:02:44.900 you how to use one particular tool and 0:02:42.050,0:02:46.459 use it well and so people have really 0:02:44.900,0:02:48.500 strong opinions about editor so you can 0:02:46.459,0:02:52.040 see the course notes for more links on 0:02:48.500,0:02:54.080 this topic looking at which editors have 0:02:52.040,0:02:56.660 been popular over the years Stack 0:02:54.080,0:02:59.090 Overflow I'm sure you've all heard of 0:02:56.660,0:03:00.320 that does a survey every year asking 0:02:59.090,0:03:02.000 developers various questions and one 0:03:00.320,0:03:03.440 thing to ask is which TextEdit Derk do 0:03:02.000,0:03:05.300 you use and it seems to be that 0:03:03.440,0:03:07.730 currently the most popular kind of 0:03:05.300,0:03:10.160 graphical editor is vs code and the most 0:03:07.730,0:03:12.440 popular editor that is based within a 0:03:10.160,0:03:13.910 command line interface is vim and so 0:03:12.440,0:03:16.040 we're going to be teaching you vim and 0:03:13.910,0:03:17.810 there a couple reasons for this one is 0:03:16.040,0:03:19.970 that all the instructors so me John and 0:03:17.810,0:03:21.320 Jose use vim as our primary editor and 0:03:19.970,0:03:23.150 we've been doing this for many years and 0:03:21.320,0:03:25.010 we've been very happy with it 0:03:23.150,0:03:28.820 and we think that there are a lot of 0:03:25.010,0:03:30.500 interesting ideas behind them so even if 0:03:28.820,0:03:32.450 you don't end up using this particular 0:03:30.500,0:03:35.540 tool in the long term I think it's 0:03:32.450,0:03:37.280 valuable to learn these ideas and also a 0:03:35.540,0:03:39.200 lot of tools have actually been really 0:03:37.280,0:03:42.200 excited about the ideas in vim and so 0:03:39.200,0:03:44.360 they support a vim emulation mode for 0:03:42.200,0:03:45.820 example vs code what's apparently the 0:03:44.360,0:03:48.170 most popular editor in use today 0:03:45.820,0:03:50.660 supports vim bindings and this vim 0:03:48.170,0:03:53.630 emulation mode as of now has like 1.4 0:03:50.660,0:03:56.450 million downloads and as you'll see over 0:03:53.630,0:03:57.830 the course of this lecture a lot of 0:03:56.450,0:03:59.570 different tools like including your 0:03:57.830,0:04:01.730 shell including things like the Python 0:03:59.570,0:04:03.200 repple and like Jupiter notebook and all 0:04:01.730,0:04:04.940 sorts of other things even your web 0:04:03.200,0:04:06.890 browser can support of emulation mode 0:04:04.940,0:04:10.400 and so yeah we're going to be teaching 0:04:06.890,0:04:12.140 you this really neat tool today and in 0:04:10.400,0:04:14.390 this lecture we can't really cover all 0:04:12.140,0:04:17.030 of them right it's a very powerful tool 0:04:14.390,0:04:18.769 but our goal is to teach you and the 0:04:17.030,0:04:20.720 core philosophy of them like the really 0:04:18.769,0:04:22.370 neat ideas behind it and then in 0:04:20.720,0:04:23.750 addition to that some of the basics like 0:04:22.370,0:04:25.490 how do you open a file close a file 0:04:23.750,0:04:27.010 navigate around a file make edits and 0:04:25.490,0:04:28.630 things like that and 0:04:27.010,0:04:29.950 you may not remember every single little 0:04:28.630,0:04:31.030 detail from this lecture because we're 0:04:29.950,0:04:32.860 gonna go pretty fast through some of the 0:04:31.030,0:04:34.510 material but it's all in the lecture 0:04:32.860,0:04:36.640 notes and then the exercises actually 0:04:34.510,0:04:37.900 give you links to some tutorials and 0:04:36.640,0:04:40.030 things so I highly recommend that you 0:04:37.900,0:04:43.840 actually go through all the exercises at 0:04:40.030,0:04:49.450 least the non advanced exercises any 0:04:43.840,0:04:51.250 questions so far great okay so one of 0:04:49.450,0:04:54.160 the really cool ideas behind them is 0:04:51.250,0:04:56.080 that vim is a modal editor what does 0:04:54.160,0:04:58.450 this mean modal comes from the word mode 0:04:56.080,0:05:00.970 and this means that vim has multiple 0:04:58.450,0:05:02.920 operating modes and this is kind of 0:05:00.970,0:05:04.570 developed from the idea that when you're 0:05:02.920,0:05:05.950 programming there often times where 0:05:04.570,0:05:07.420 you're doing different types of things 0:05:05.950,0:05:09.220 like sometimes you're reading code 0:05:07.420,0:05:10.960 sometimes you're making small edits to 0:05:09.220,0:05:12.340 code like you're finding a particular 0:05:10.960,0:05:15.040 point like changing a little thing 0:05:12.340,0:05:16.540 somewhere sometimes you're just writing 0:05:15.040,0:05:17.470 a lot of code in one go like suppose 0:05:16.540,0:05:19.090 you're just writing a function from 0:05:17.470,0:05:20.380 scratch and so there's different 0:05:19.090,0:05:24.070 operating modes for doing these 0:05:20.380,0:05:25.180 different types of things and so I'm 0:05:24.070,0:05:26.470 actually want to write this down on the 0:05:25.180,0:05:28.780 blackboard so I'll have a useful thing 0:05:26.470,0:05:33.280 to refer to later so when you start vim 0:05:28.780,0:05:35.260 up it starts up in what's called normal 0:05:33.280,0:05:37.270 mode and in this mode all the different 0:05:35.260,0:05:38.650 key combinations behave in one way and 0:05:37.270,0:05:40.030 then there are different key 0:05:38.650,0:05:42.400 combinations that switch you between 0:05:40.030,0:05:45.880 normal mode and other modes which change 0:05:42.400,0:05:47.950 the meaning of different keys so for the 0:05:45.880,0:05:49.870 most part you'll be spending most of 0:05:47.950,0:05:55.420 your time in vim in normal mode or what 0:05:49.870,0:05:57.400 is called insert mode and to go to 0:05:55.420,0:05:59.530 insert mode you press the key I for 0:05:57.400,0:06:01.600 normal mode and to go from insert mode 0:05:59.530,0:06:06.700 back to normal mode you press the Escape 0:06:01.600,0:06:09.580 key a little note on notation because 0:06:06.700,0:06:11.020 we'll need this later in the notation 0:06:09.580,0:06:12.610 I'm going to be using in this lecture 0:06:11.020,0:06:15.100 and what's also in the lecture notes and 0:06:12.610,0:06:16.150 what vim uses to give you feedback they 0:06:15.100,0:06:17.740 have a couple different ways of talking 0:06:16.150,0:06:19.270 about different keys so when they're 0:06:17.740,0:06:20.440 talking about bare keys like just the 0:06:19.270,0:06:22.660 eye key on your keyboard they'll just 0:06:20.440,0:06:24.310 say eye but for a different key 0:06:22.660,0:06:27.130 combinations like when you press control 0:06:24.310,0:06:29.920 and something like say control V it's 0:06:27.130,0:06:32.350 notated in one of like approximately 0:06:29.920,0:06:34.600 three ways one way that can be notated 0:06:32.350,0:06:37.480 is a caret and then the control 0:06:34.600,0:06:39.580 character so this is control V another 0:06:37.480,0:06:40.660 way this might be written I think we've 0:06:39.580,0:06:42.250 written it this way in 0:06:40.660,0:06:43.150 lecture notes as control-v this is 0:06:42.250,0:06:46.060 probably the one you're more used to 0:06:43.150,0:06:48.880 seeing and then in some parts of them 0:06:46.060,0:06:51.010 this is written as angle brackets C - V 0:06:48.880,0:06:54.210 close angle bracket so just a little bit 0:06:51.010,0:06:54.210 of notation that will be useful later 0:06:54.220,0:06:59.350 so yeah vim has a couple different modes 0:06:56.950,0:07:01.540 where normal mode is designed for 0:06:59.350,0:07:03.520 navigating around a file reading things 0:07:01.540,0:07:05.620 going from file to file things like that 0:07:03.520,0:07:08.380 and then insert mode is where you type 0:07:05.620,0:07:10.330 in text so most keys that you press here 0:07:08.380,0:07:12.040 will just go into your text buffer where 0:07:10.330,0:07:13.780 as keys that you press here are not 0:07:12.040,0:07:15.190 being put into the buffer and instead 0:07:13.780,0:07:20.380 are used for things like navigation or 0:07:15.190,0:07:21.520 making edits and actually the picture is 0:07:20.380,0:07:23.200 a little bit more complicated than this 0:07:21.520,0:07:24.370 there are a whole bunch of other modes 0:07:23.200,0:07:25.900 and I'm just gonna write them down here 0:07:24.370,0:07:29.050 because we'll have them here to refer to 0:07:25.900,0:07:33.100 later and so if it also has a replace 0:07:29.050,0:07:34.030 mode for rather than inserting text and 0:07:33.100,0:07:36.160 kind of pushing what's ahead of it 0:07:34.030,0:07:37.810 forward it will overwrite text and then 0:07:36.160,0:07:44.920 it has a bunch of different modes for 0:07:37.810,0:07:48.040 selection so it has a mode called visual 0:07:44.920,0:07:53.710 mode and then it has visual line and 0:07:48.040,0:07:57.040 visual block this one is enter via the R 0:07:53.710,0:08:01.810 key this was entered via the V key this 0:07:57.040,0:08:05.680 one is entered via shift B and this one 0:08:01.810,0:08:13.300 is entered via control V and then 0:08:05.680,0:08:17.430 there's the command line mode which is 0:08:13.300,0:08:17.430 entered via the colon key 0:08:19.180,0:08:31.300 okay so now that we have that on the 0:08:21.070,0:08:35.230 board to refer to later we can actually 0:08:31.300,0:08:36.340 try some of this out all right so one 0:08:35.230,0:08:38.560 thing we noticed looking at that picture 0:08:36.340,0:08:40.390 is that to go from normal mode to any of 0:08:38.560,0:08:41.800 the other modes we press some key but to 0:08:40.390,0:08:43.330 go from any of the other modes back to 0:08:41.800,0:08:45.190 normal mode where we spend a lot of our 0:08:43.330,0:08:48.640 time we use the Escape key on our 0:08:45.190,0:08:49.960 keyboard so for this reason since you 0:08:48.640,0:08:51.970 under pressing the Escape key a lot when 0:08:49.960,0:08:53.650 using vim a lot of programmers rebind 0:08:51.970,0:08:55.180 one of the keys on their keyboard to be 0:08:53.650,0:08:56.620 escape because it's really inconvenient 0:08:55.180,0:08:58.060 to reach up with your left pinkie to 0:08:56.620,0:08:59.920 press that tiny little Escape key in the 0:08:58.060,0:09:01.870 corner of your keyboard and so a lot of 0:08:59.920,0:09:04.540 people use the caps lock key instead so 0:09:01.870,0:09:06.580 it's right there in the home row and we 0:09:04.540,0:09:14.380 have some links in the lecture notes for 0:09:06.580,0:09:15.730 how you can do this key rebinding okay 0:09:14.380,0:09:17.500 so now that we've talked about kind of 0:09:15.730,0:09:19.300 one of the core ideas of vim the idea of 0:09:17.500,0:09:20.830 modal editing we can talk about some of 0:09:19.300,0:09:23.080 the basics like how do you open up this 0:09:20.830,0:09:25.870 text editor how do you open file save 0:09:23.080,0:09:28.240 files and things like that and so this 0:09:25.870,0:09:29.740 is a command line based program although 0:09:28.240,0:09:31.900 there are some graphical variants and 0:09:29.740,0:09:34.420 the way you start this program is by 0:09:31.900,0:09:35.800 running vim one thing you might notice 0:09:34.420,0:09:37.510 is that in the bottom left corner of my 0:09:35.800,0:09:40.090 screen they actually saw what I just 0:09:37.510,0:09:41.530 typed this will be useful later in this 0:09:40.090,0:09:44.020 lecture where I'm actually typing in 0:09:41.530,0:09:45.370 commands for vim and I'll be saying what 0:09:44.020,0:09:47.890 I'm typing but you'll also see it on the 0:09:45.370,0:09:50.380 screen so if I press ctrl C see it says 0:09:47.890,0:09:55.510 ctrl C over there is that text big 0:09:50.380,0:09:57.610 enough for everybody to read great okay 0:09:55.510,0:09:59.800 so the way we open vim is just by 0:09:57.610,0:10:02.470 running the program vim on our command 0:09:59.800,0:10:03.790 line and this comes pre-installed on 0:10:02.470,0:10:05.020 most systems and if you don't have it 0:10:03.790,0:10:07.600 you can install it using your package 0:10:05.020,0:10:08.560 manager vim can also take an argument if 0:10:07.600,0:10:10.570 we want to use it to edit a particular 0:10:08.560,0:10:12.850 file instead of just opening up the 0:10:10.570,0:10:15.310 program then later opening a file so for 0:10:12.850,0:10:17.140 example I have a file in this directory 0:10:15.310,0:10:19.690 this is actually the lecture notes for 0:10:17.140,0:10:21.940 this lecture so I can do vim editors MD 0:10:19.690,0:10:25.690 and press ENTER and then boom them is 0:10:21.940,0:10:29.820 started and then in this lecture I'm not 0:10:25.690,0:10:32.860 running vim in the completely Exton I've 0:10:29.820,0:10:34.930 configured a couple of things that 0:10:32.860,0:10:36.940 behave a little bit nicer by defaults 0:10:34.930,0:10:38.410 little things like having line numbers 0:10:36.940,0:10:40.210 on the left or having some more status 0:10:38.410,0:10:41.140 information on the bottom and if you 0:10:40.210,0:10:42.850 want to start with this default 0:10:41.140,0:10:43.930 configuration we have a link to this in 0:10:42.850,0:10:49.270 the lecture notes so you can get a 0:10:43.930,0:10:51.250 slightly more sane config by default so 0:10:49.270,0:10:53.290 once you've opened them what do you do 0:10:51.250,0:10:54.580 well as I said earlier vim starts in 0:10:53.290,0:10:57.880 normal mode so if I just start typing 0:10:54.580,0:10:59.650 letters like say type X it didn't insert 0:10:57.880,0:11:01.660 X into the buffer you can see the cursor 0:10:59.650,0:11:03.610 up in the top left it actually deleted 0:11:01.660,0:11:07.300 one of the characters that's because I'm 0:11:03.610,0:11:08.620 in normal mode not insert mode so insert 0:11:07.300,0:11:09.850 mode is basically what you used to with 0:11:08.620,0:11:10.900 all the other text editors you've used 0:11:09.850,0:11:12.310 in the past where there's a cursor 0:11:10.900,0:11:15.310 somewhere you press the character and it 0:11:12.310,0:11:18.130 just goes into your buffer I'm instead 0:11:15.310,0:11:19.900 in vim you start a normal mode and you 0:11:18.130,0:11:21.610 can press I to go into insert mode so 0:11:19.900,0:11:23.980 see I've pressed I and then in the 0:11:21.610,0:11:26.500 bottom left notice that it says - - 0:11:23.980,0:11:27.850 insert the bottom left always tells you 0:11:26.500,0:11:29.650 what mode you're in unless this normal 0:11:27.850,0:11:31.270 mode in which case it's blank and now 0:11:29.650,0:11:33.250 that I'm an insert mode if I press the X 0:11:31.270,0:11:35.740 character for example see it just gets 0:11:33.250,0:11:37.450 inserted into my text buffer and I can 0:11:35.740,0:11:39.580 backspace over at type other stuff and 0:11:37.450,0:11:41.400 now my text editor kind of behaves like 0:11:39.580,0:11:43.780 you'd expect any other program to behave 0:11:41.400,0:11:45.520 so from this point how to go back to 0:11:43.780,0:11:48.910 normal mode if I want to stop inserting 0:11:45.520,0:11:51.670 characters yes exactly I press escape 0:11:48.910,0:11:53.830 and that's the symbol my keystroke 0:11:51.670,0:11:58.960 visuals I visualizer uses for escape so 0:11:53.830,0:12:01.150 just be aware of that and then vim has 0:11:58.960,0:12:02.890 this idea that using the mouse is 0:12:01.150,0:12:04.570 inefficient like your hands are on the 0:12:02.890,0:12:06.460 keyboard moving your hand over to the 0:12:04.570,0:12:08.290 mouse takes a lot of time right like you 0:12:06.460,0:12:09.610 don't want to waste those couple of 0:12:08.290,0:12:11.410 milliseconds while you're programming 0:12:09.610,0:12:13.990 like in the middle of things so instead 0:12:11.410,0:12:15.700 all vim functionality can be accessed 0:12:13.990,0:12:16.780 just through the keyboard and it's all 0:12:15.700,0:12:19.330 sorts of things you might be used to 0:12:16.780,0:12:21.460 doing like opening files by going like 0:12:19.330,0:12:23.050 file open or file save or things like 0:12:21.460,0:12:25.450 that or instead access through the 0:12:23.050,0:12:27.520 keyboard and how is that done that's 0:12:25.450,0:12:28.690 done through one of the other vim modes 0:12:27.520,0:12:31.960 that are on the board over there in 0:12:28.690,0:12:33.850 particular through command line mode so 0:12:31.960,0:12:36.370 if you're in normal mode and you press 0:12:33.850,0:12:39.370 the colon key you'll notice that the 0:12:36.370,0:12:41.320 cursor I guess my visualizer is covering 0:12:39.370,0:12:43.060 the thing right now but it's gone the 0:12:41.320,0:12:46.110 cursor jumps to the bottom the bottom 0:12:43.060,0:12:48.510 left and it shows that : I just typed 0:12:46.110,0:12:50.220 now I can type in a command so you can 0:12:48.510,0:12:51.570 think of this almost like the command 0:12:50.220,0:12:53.160 shell that we've talked been talking 0:12:51.570,0:12:54.029 about over the last few days except this 0:12:53.160,0:12:55.800 is VIMS 0:12:54.029,0:12:57.200 command shell so you give vim commands 0:12:55.800,0:12:59.339 here instead of shell commands and 0:12:57.200,0:13:00.600 they're a bunch of built-in commands 0:12:59.339,0:13:02.820 that do all the things that you're used 0:13:00.600,0:13:04.260 to like for example one command that you 0:13:02.820,0:13:05.670 might want to know is how to quit this 0:13:04.260,0:13:07.440 editor you might notice that if your 0:13:05.670,0:13:08.730 normal mode I can press escape to go 0:13:07.440,0:13:11.940 back from command line mode to normal 0:13:08.730,0:13:13.560 mode and I press control C I'm like what 0:13:11.940,0:13:16.019 happens the lot of programs this doesn't 0:13:13.560,0:13:18.360 quit them so how do I quit vim I can 0:13:16.019,0:13:19.860 press colon and then go into command 0:13:18.360,0:13:23.430 line mode and then I can type in the 0:13:19.860,0:13:24.870 command quit key uit you'll see that I 0:13:23.430,0:13:28.560 maybe I should move this over to the 0:13:24.870,0:13:31.350 middle or something ceases colon quit 0:13:28.560,0:13:32.910 and I press ENTER and it quits bin I can 0:13:31.350,0:13:35.490 open him up again there's actually a 0:13:32.910,0:13:38.430 short form for this command just : Q and 0:13:35.490,0:13:40.019 that'll do the same thing and there a 0:13:38.430,0:13:42.839 bunch of other useful commands like this 0:13:40.019,0:13:45.149 so some other handy wants to know are 0:13:42.839,0:13:47.790 how do you save a file so suppose I make 0:13:45.149,0:13:51.420 some edits here like hello world 0:13:47.790,0:13:53.970 so I pressed I to go into insert mode or 0:13:51.420,0:13:55.560 let me redo that I press I to go into 0:13:53.970,0:14:02.010 insert mode right now I can use the down 0:13:55.560,0:14:03.240 arrow to oh hey I think I've slightly I 0:14:02.010,0:14:07.019 should fix that can you fix the config 0:14:03.240,0:14:11.730 actually John never mind that 0:14:07.019,0:14:14.820 okay so I suppose I go down to this line 0:14:11.730,0:14:17.010 and I press I to go into insert mode and 0:14:14.820,0:14:18.930 type in some text and then press escape 0:14:17.010,0:14:20.610 to go back to normal mode now how do I 0:14:18.930,0:14:22.680 actually save this file well there's 0:14:20.610,0:14:25.550 another command for that so colon to go 0:14:22.680,0:14:30.480 into command mode and then I can type W 0:14:25.550,0:14:33.240 and press Enter w stands for write and 0:14:30.480,0:14:35.699 it says in the bottom editors MD 0:14:33.240,0:14:37.829 whatever blah blah written and so this 0:14:35.699,0:14:40.320 means it saved the file and so now if I 0:14:37.829,0:14:42.209 colon Q to quit and open the same file 0:14:40.320,0:14:46.850 again you'll see that the changes have 0:14:42.209,0:14:49.019 been persisted there are a couple other 0:14:46.850,0:14:50.130 there's so there's a ton of different 0:14:49.019,0:14:53.070 vim commands that are useful for 0:14:50.130,0:14:56.100 different reasons but I'll just explain 0:14:53.070,0:14:59.070 a couple more to you now one command 0:14:56.100,0:15:01.500 that's really useful is help colon help 0:14:59.070,0:15:04.080 and you can do : help and then type in a 0:15:01.500,0:15:06.090 particular key or a particular command 0:15:04.080,0:15:08.580 and get help for that keystroke or that 0:15:06.090,0:15:10.950 command so if I want to know what : that 0:15:08.580,0:15:15.420 was if I want to know what : w does I 0:15:10.950,0:15:21.300 can do : help : W and that'll give me 0:15:15.420,0:15:23.160 the documentation on : w or : right if I 0:15:21.300,0:15:25.560 do : q it'll close this window and bring 0:15:23.160,0:15:28.530 me back to where I was before 0:15:25.560,0:15:35.340 and notice that : help : w is different 0:15:28.530,0:15:38.190 from : help W because the W key is the W 0:15:35.340,0:15:40.590 that like when you're normal mode and 0:15:38.190,0:15:41.670 press W what happens is just the W key 0:15:40.590,0:15:43.530 here without the : 0:15:41.670,0:15:50.340 and if I look for help for : W that's 0:15:43.530,0:15:56.040 the help for the W command so now you 0:15:50.340,0:15:58.110 basically have the bare fundamentals 0:15:56.040,0:16:00.720 needed to use them right you can open 0:15:58.110,0:16:03.180 the editor use it to edit a particular 0:16:00.720,0:16:05.010 file press I to go into insert mode and 0:16:03.180,0:16:06.840 type in some text press escape to go 0:16:05.010,0:16:09.630 back to normal mode and then : W to save 0:16:06.840,0:16:11.460 your changes : W to quit so like already 0:16:09.630,0:16:13.920 you have the bare fundamentals necessary 0:16:11.460,0:16:17.210 to edit files using them albeit somewhat 0:16:13.920,0:16:23.700 inefficiently so any questions so far 0:16:17.210,0:16:25.470 yeah in the back yeah so the question is 0:16:23.700,0:16:27.060 what's the benefit of the nura of the 0:16:25.470,0:16:28.590 normal mode and we'll talk about that in 0:16:27.060,0:16:31.560 more detail in like five minutes 0:16:28.590,0:16:33.030 but in short insert mode is just for 0:16:31.560,0:16:34.920 typing in text so I'm an insert mode I 0:16:33.030,0:16:36.270 can type in text but when I'm 0:16:34.920,0:16:39.000 programming I actually spend a lot of 0:16:36.270,0:16:40.590 time moving around my file making small 0:16:39.000,0:16:42.210 little changes so I go here and like oh 0:16:40.590,0:16:45.390 maybe I want to change this HTTP link to 0:16:42.210,0:16:48.120 an HD HTTP to HTTP 0:16:45.390,0:16:49.920 I can make like small point edits things 0:16:48.120,0:16:51.120 like that in normal mode and we'll see a 0:16:49.920,0:16:52.920 whole lot more of that in about five 0:16:51.120,0:16:59.130 minutes good question 0:16:52.920,0:17:05.070 any other questions okay cool so moving 0:16:59.130,0:17:11.100 along one other thing that's kind of 0:17:05.070,0:17:12.720 useful to know I think is at a high 0:17:11.100,0:17:15.479 level VIMS model 0:17:12.720,0:17:16.470 buffers versus windows versus tabs so 0:17:15.479,0:17:17.939 it's probably the case that whatever 0:17:16.470,0:17:19.829 program you were using before like 0:17:17.939,0:17:21.899 sublime text or vs code or whatever 0:17:19.829,0:17:23.249 you could open multiple files in it 0:17:21.899,0:17:24.899 right and you could probably have 0:17:23.249,0:17:27.449 multiple tabs open and have multiple 0:17:24.899,0:17:29.129 windows open of your editor so vim also 0:17:27.449,0:17:31.200 has a notion of those different things 0:17:29.129,0:17:34.379 but it's models a little bit different 0:17:31.200,0:17:36.359 than most other programs so vim 0:17:34.379,0:17:38.340 maintains a set of open buffers that's 0:17:36.359,0:17:40.320 the word it uses for open files and so 0:17:38.340,0:17:42.239 it has a set of open files and then kind 0:17:40.320,0:17:44.489 of separately from that you can have a 0:17:42.239,0:17:46.619 number of tabs and tabs can have windows 0:17:44.489,0:17:47.460 the kind of weird thing which makes them 0:17:46.619,0:17:48.899 a little bit different than the 0:17:47.460,0:17:50.729 programming probably used in the past is 0:17:48.899,0:17:52.049 that there isn't necessarily a 0:17:50.729,0:17:55.200 one-to-one correspondence between 0:17:52.049,0:17:56.669 buffers and windows so one thing I can 0:17:55.200,0:17:58.259 do for example here and we'll show you 0:17:56.669,0:18:00.989 the key combinations and stuff for this 0:17:58.259,0:18:02.220 later but one thing you can do is create 0:18:00.989,0:18:04.109 two different windows so I have one 0:18:02.220,0:18:07.139 window up here and then one window down 0:18:04.109,0:18:08.609 here and notice that the same files open 0:18:07.139,0:18:10.529 in both windows so if I make some edits 0:18:08.609,0:18:11.759 over here they actually happen in the 0:18:10.529,0:18:13.729 bottom window as well because it's the 0:18:11.759,0:18:16.590 same buffer that's open in both windows 0:18:13.729,0:18:18.269 and this is kind of useful for say 0:18:16.590,0:18:19.830 looking at two different parts of a 0:18:18.269,0:18:20.940 single file at the same time like so you 0:18:19.830,0:18:22.919 want to be able to look at the top of a 0:18:20.940,0:18:25.049 file say at an import to your program 0:18:22.919,0:18:27.809 while you're down below working 0:18:25.049,0:18:29.129 somewhere else so this is one helpful 0:18:27.809,0:18:32.999 thing to keep in mind that vim has this 0:18:29.129,0:18:35.729 idea of they're a number of tabs and 0:18:32.999,0:18:38.159 each tab has some number of Windows and 0:18:35.729,0:18:40.649 then each window has a corresponds to 0:18:38.159,0:18:42.269 some buffer but a particular buffer can 0:18:40.649,0:18:44.399 be open in zero or more windows at a 0:18:42.269,0:18:45.809 time just one thing that confused me 0:18:44.399,0:18:48.049 when I was initially learning BIM so I 0:18:45.809,0:18:50.669 want to explain that early on and then 0:18:48.049,0:18:53.580 the : Q command which we talked about 0:18:50.669,0:18:55.349 earlier is not exactly quit it's kind of 0:18:53.580,0:18:56.729 closed the current window and then when 0:18:55.349,0:18:59.460 they're no more open windows then we'll 0:18:56.729,0:19:01.320 quit so here if I do : Q it'll only 0:18:59.460,0:19:03.570 close the window I think on the top here 0:19:01.320,0:19:05.609 because that's the one I was in and now 0:19:03.570,0:19:08.159 the remaining window becomes fullscreen 0:19:05.609,0:19:10.379 I can do : Q again to close this now in 0:19:08.159,0:19:14.879 the second tab that I'd open if I do : Q 0:19:10.379,0:19:16.229 a final time okay now vim exits and if 0:19:14.879,0:19:17.940 you don't want to press : Q way too many 0:19:16.229,0:19:21.419 times okay so here I have three split 0:19:17.940,0:19:24.589 windows if I do : QA for quit all it 0:19:21.419,0:19:24.589 closes all the open windows 0:19:25.370,0:19:30.660 all right so now answer your question of 0:19:28.650,0:19:32.610 what is normal mode actually for this is 0:19:30.660,0:19:34.080 another really cool idea in them and I 0:19:32.610,0:19:36.030 think this is actually like the most 0:19:34.080,0:19:38.550 fundamentally interesting idea of this 0:19:36.030,0:19:42.000 program it's that like you're all 0:19:38.550,0:19:44.370 programmers you like programming vim has 0:19:42.000,0:19:47.220 this idea that VIMS normal mode like 0:19:44.370,0:19:49.740 VIMS interface itself is a programming 0:19:47.220,0:19:51.060 language well and let me repeat that 0:19:49.740,0:19:52.860 that's like a kind of fundamentally 0:19:51.060,0:19:54.020 interesting idea the interface is a 0:19:52.860,0:19:56.250 programming language 0:19:54.020,0:19:57.570 what does that mean it means that 0:19:56.250,0:19:59.280 different key combinations have 0:19:57.570,0:20:00.150 different effects and once you learn the 0:19:59.280,0:20:02.400 different effects you can actually 0:20:00.150,0:20:03.390 combine them together just like in a 0:20:02.400,0:20:04.770 programming language you can learn 0:20:03.390,0:20:05.880 different functions and stuff and then 0:20:04.770,0:20:08.070 glue them all together to make an 0:20:05.880,0:20:09.870 interesting program in the same way once 0:20:08.070,0:20:10.980 you learn them's different movement and 0:20:09.870,0:20:13.890 editing commands and things like that 0:20:10.980,0:20:16.950 you can talk to them by programming vim 0:20:13.890,0:20:19.170 through its interface and once this 0:20:16.950,0:20:20.880 becomes muscle memory you can basically 0:20:19.170,0:20:22.440 edit files at the speed at which you 0:20:20.880,0:20:23.640 think like at least for me I don't think 0:20:22.440,0:20:25.320 I've been able to do this with any other 0:20:23.640,0:20:29.010 text editor that I've used in the past 0:20:25.320,0:20:31.380 but this one gets pretty close so let's 0:20:29.010,0:20:34.170 dig into how exactly normal mode works 0:20:31.380,0:20:36.140 so you can try to follow along with this 0:20:34.170,0:20:38.400 like open up some random file in vim and 0:20:36.140,0:20:40.470 follow some of the key combinations I 0:20:38.400,0:20:42.330 type in so one basic thing that you 0:20:40.470,0:20:44.010 might want to do is just navigate around 0:20:42.330,0:20:46.020 a buffer like move your cursor up down 0:20:44.010,0:20:48.510 left right and so the way you do that in 0:20:46.020,0:20:50.700 vim is using the hjkl keys not the arrow 0:20:48.510,0:20:52.050 keys though they do work by default try 0:20:50.700,0:20:53.520 to avoid them because you don't want to 0:20:52.050,0:20:54.660 have to move your hand all the way over 0:20:53.520,0:20:57.240 to the arrow keys like there's a ton of 0:20:54.660,0:21:00.510 time you're wasting right HT Cales right 0:20:57.240,0:21:04.020 on the home row and so J moves down K 0:21:00.510,0:21:06.390 moves up H moves left and L moves right 0:21:04.020,0:21:08.940 and this may seem a little unintuitive 0:21:06.390,0:21:10.410 now there was some historical reason for 0:21:08.940,0:21:13.440 it like the keyboard the original VI 0:21:10.410,0:21:14.910 developer used had the hjkl keys like 0:21:13.440,0:21:17.040 labeled and arranged in a way that made 0:21:14.910,0:21:19.260 this more reasonable but this will very 0:21:17.040,0:21:20.370 soon become muscle memory so this is the 0:21:19.260,0:21:24.270 basic way you can move your cursor 0:21:20.370,0:21:26.070 around while in normal mode now what 0:21:24.270,0:21:27.720 else can you do well if we had to move 0:21:26.070,0:21:29.820 around files like this it'll be really 0:21:27.720,0:21:31.590 slow we don't have to want to have to 0:21:29.820,0:21:33.210 hold down these keys and like wait for a 0:21:31.590,0:21:34.350 long time for them to do its thing and 0:21:33.210,0:21:35.760 so there are all these other different 0:21:34.350,0:21:36.650 key combinations for doing different 0:21:35.760,0:21:38.120 movements 0:21:36.650,0:21:39.200 also by the way this is all in the 0:21:38.120,0:21:40.940 lecture notes so you don't need to 0:21:39.200,0:21:43.550 memorize every single key and its 0:21:40.940,0:21:45.320 meaning right now just try to understand 0:21:43.550,0:21:47.570 the overall idea that bins interface is 0:21:45.320,0:21:50.000 a programming language so another thing 0:21:47.570,0:21:52.820 you can do is press the W key this moves 0:21:50.000,0:21:54.620 the cursor forward by one word and then 0:21:52.820,0:21:57.740 similarly the B key moves the cursor 0:21:54.620,0:21:59.360 backward by one word so this allows 0:21:57.740,0:22:01.820 slightly more efficient movement within 0:21:59.360,0:22:04.010 the line there's also the e key for 0:22:01.820,0:22:06.620 moving to the end of a word you're gonna 0:22:04.010,0:22:08.030 move this over a little bit so if I'm 0:22:06.620,0:22:09.800 here for example and I press the e key 0:22:08.030,0:22:12.850 it'll go to the end of this word end of 0:22:09.800,0:22:15.980 this word end of the next word and so on 0:22:12.850,0:22:17.720 you can also move by whole lines so zero 0:22:15.980,0:22:19.760 moves to the beginning of a line dollar 0:22:17.720,0:22:22.640 sign moves to the end of a line and the 0:22:19.760,0:22:25.790 caret key moves to the first non-empty 0:22:22.640,0:22:31.730 character on a line so let me find one 0:22:25.790,0:22:33.590 of those for example so here I'm on my 0:22:31.730,0:22:34.760 cursors right here if I press 0 my 0:22:33.590,0:22:37.040 cursor goes to the beginning of the line 0:22:34.760,0:22:39.590 dollar sign end of the current line and 0:22:37.040,0:22:41.270 if I press caret we're like on what 0:22:39.590,0:22:44.840 character will the curser end up can 0:22:41.270,0:22:47.870 anybody guess so caret goes to the first 0:22:44.840,0:22:53.000 non-empty character on a line kind of 0:22:47.870,0:22:57.200 like reg X carrot yeah exactly it goes 0:22:53.000,0:22:59.780 to this - let's talk about some more 0:22:57.200,0:23:01.220 movement commands there's a ways to 0:22:59.780,0:23:06.230 scroll up and down in a buffer so 0:23:01.220,0:23:08.510 control U goes up and control D scroll 0:23:06.230,0:23:10.850 down so this is better than holding down 0:23:08.510,0:23:13.190 the K or J keys for example this is a 0:23:10.850,0:23:17.720 lot slower than moving by entire pages 0:23:13.190,0:23:19.970 control D and control you there's also 0:23:17.720,0:23:22.400 ways to move by the entire buffer so 0:23:19.970,0:23:26.420 capital G moves all the way down G G 0:23:22.400,0:23:28.490 moves all the way up some of these 0:23:26.420,0:23:29.600 movement keys are mnemonics so they're 0:23:28.490,0:23:31.400 like a little bit easier to remember for 0:23:29.600,0:23:33.440 that reason right like double use word B 0:23:31.400,0:23:36.230 as beginning for it is end of word those 0:23:33.440,0:23:38.030 all seem pretty logical 0 caret and 0:23:36.230,0:23:39.559 dollar kind of inspired from reg X so 0:23:38.030,0:23:41.120 those make a little bit of sense there's 0:23:39.559,0:23:42.890 some other ones that like don't 0:23:41.120,0:23:43.940 necessarily make way too much sense but 0:23:42.890,0:23:46.310 there are only so many keys on your 0:23:43.940,0:23:48.590 keyboard so what are you going to do for 0:23:46.310,0:23:49.430 example the L key moves your cursor to 0:23:48.590,0:23:51.890 the lowest 0:23:49.430,0:23:54.920 line that's shown on the screen l4 0:23:51.890,0:24:01.430 lowest makes sense m4 middle and then h4 0:23:54.920,0:24:02.660 highest I guess no and there's a whole 0:24:01.430,0:24:04.250 bunch of other interesting movements 0:24:02.660,0:24:05.330 like this so we're obviously not going 0:24:04.250,0:24:07.070 to be able to cover all of them right 0:24:05.330,0:24:08.690 now but you'll be able to go through 0:24:07.070,0:24:11.320 them in the vim tutor exercise which is 0:24:08.690,0:24:15.790 exercise number one for this lecture 0:24:11.320,0:24:18.080 some other ones I want to talk about now 0:24:15.790,0:24:19.640 maybe I'll talk about one more there's 0:24:18.080,0:24:21.440 another movement called find this is 0:24:19.640,0:24:23.210 also kind of useful suppose I'm on this 0:24:21.440,0:24:25.340 line and I want to jump to the first 0:24:23.210,0:24:27.260 character that equal to something like I 0:24:25.340,0:24:31.310 want to jump to the first oh I can press 0:24:27.260,0:24:33.860 F oh and my cursor moves to the first 0:24:31.310,0:24:35.210 oh I've like found oh I can do FW and 0:24:33.860,0:24:39.560 it'll move to the first W which I think 0:24:35.210,0:24:40.880 is right here F C find the first C I can 0:24:39.560,0:24:44.510 also do the same thing but backwards if 0:24:40.880,0:24:47.930 I do capital F W I can find the W that's 0:24:44.510,0:24:49.760 before it a capital FS find the s that's 0:24:47.930,0:24:53.450 before that and then there's a variant 0:24:49.760,0:24:56.690 of F for find T for two so I can jump to 0:24:53.450,0:24:58.520 O and it jumps like until it's found oh 0:24:56.690,0:25:03.110 but not on top of it right before it and 0:24:58.520,0:25:04.820 capital T say T jumps backwards to the T 0:25:03.110,0:25:07.190 except not all the way on top of it one 0:25:04.820,0:25:09.770 character before and so you can already 0:25:07.190,0:25:10.970 see that idea I talked about of like vim 0:25:09.770,0:25:13.160 is a programming language you can really 0:25:10.970,0:25:15.050 compose these commands F and T are 0:25:13.160,0:25:16.790 finding two and you can say find a 0:25:15.050,0:25:20.180 particular character or jump to a 0:25:16.790,0:25:22.400 particular character so those are a 0:25:20.180,0:25:26.660 couple of them movement commands so any 0:25:22.400,0:25:32.050 questions about those so far so this is 0:25:26.660,0:25:33.980 yeah question right yeah okay cool so 0:25:32.050,0:25:35.540 those are have been movement commands 0:25:33.980,0:25:37.880 this is how you can navigate around a 0:25:35.540,0:25:40.070 file quickly in normal mode now another 0:25:37.880,0:25:42.770 category of useful commands are editing 0:25:40.070,0:25:44.480 commands so one we kind of already 0:25:42.770,0:25:46.520 talked about which is the eye command 0:25:44.480,0:25:48.500 for moving from normal mode to insert 0:25:46.520,0:25:50.690 mode where you can start just writing 0:25:48.500,0:25:52.490 text so suppose I go up here and I press 0:25:50.690,0:25:57.020 I now I can type in whatever text I want 0:25:52.490,0:25:58.370 hello world enter this back then press 0:25:57.020,0:26:00.890 escape to go back to normal mode and 0:25:58.370,0:26:01.640 I've made a change to my buffer but 0:26:00.890,0:26:03.740 there are a whole bunch of other 0:26:01.640,0:26:05.540 commands for making efficient 0:26:03.740,0:26:07.760 that makes sense for when you're dealing 0:26:05.540,0:26:09.410 with programming languages so one useful 0:26:07.760,0:26:10.670 command that I accidentally used earlier 0:26:09.410,0:26:13.280 before teaching you about it is the O 0:26:10.670,0:26:16.130 command so suppose my cursor is like 0:26:13.280,0:26:18.410 over here and if i press o from normal 0:26:16.130,0:26:19.490 mode what it does is it opens a new line 0:26:18.410,0:26:22.040 below where my cursor is 0:26:19.490,0:26:23.420 that's what o stands for and it so it 0:26:22.040,0:26:24.980 creates a new line and put me into 0:26:23.420,0:26:27.290 insert modes and I can start typing in 0:26:24.980,0:26:29.600 some text press escape and go back to 0:26:27.290,0:26:32.240 normal mode and then just like the O 0:26:29.600,0:26:35.540 command there's a capital o command so 0:26:32.240,0:26:37.850 if I'm here and I do capital o it puts 0:26:35.540,0:26:41.690 me into insert mode above where I 0:26:37.850,0:26:44.240 currently am there's another vim command 0:26:41.690,0:26:47.690 for deleting things so suppose my cursor 0:26:44.240,0:26:51.560 is like on top of this word right here 0:26:47.690,0:26:54.350 and I press the D key D for delete oh 0:26:51.560,0:26:55.970 nothing happens turns out that the D key 0:26:54.350,0:26:57.860 needs to be combined with a movement 0:26:55.970,0:26:59.630 command so remember we just talked about 0:26:57.860,0:27:02.870 different movement commands like hjkl 0:26:59.630,0:27:03.530 and like word and backward word and 0:27:02.870,0:27:07.670 things like that 0:27:03.530,0:27:11.600 so I press D whoops I press D and I can 0:27:07.670,0:27:13.970 press W and it's deleted a word so let 0:27:11.600,0:27:16.820 me undo that undoing vim is just you for 0:27:13.970,0:27:19.940 undo so notice my cursors right here I 0:27:16.820,0:27:21.770 do DW it's deleted a word I can move 0:27:19.940,0:27:25.100 around and then delete another word 0:27:21.770,0:27:27.620 suppose I'm keeps getting in the way 0:27:25.100,0:27:29.420 suppose I'm like somewhere in the middle 0:27:27.620,0:27:31.130 of a word and I want to delete the end 0:27:29.420,0:27:35.630 of a word any guesses for what 0:27:31.130,0:27:39.320 combination of keys I'd use for that D 0:27:35.630,0:27:43.790 and what de exactly delete the end of 0:27:39.320,0:27:46.790 the word another useful editing command 0:27:43.790,0:27:48.800 is the C command C stands for change so 0:27:46.790,0:27:50.840 change is really similar to delete 0:27:48.800,0:27:52.220 except change puts you in insert mode 0:27:50.840,0:27:54.500 because like I want to delete a thing 0:27:52.220,0:27:56.960 but change it to something else so if 0:27:54.500,0:27:59.810 I'm here and I do see e it's like change 0:27:56.960,0:28:00.950 to the end of the word and it gets rid 0:27:59.810,0:28:02.630 of the contents until the end of the 0:28:00.950,0:28:04.460 word and notice it put me in insert mode 0:28:02.630,0:28:06.740 so now whatever characters I type go 0:28:04.460,0:28:11.270 into the buffer if I press escape I go 0:28:06.740,0:28:13.250 back into normal mode and so C and D are 0:28:11.270,0:28:15.650 analogs they both take motions as 0:28:13.250,0:28:17.290 arguments and they will either delete 0:28:15.650,0:28:20.950 that motion or change 0:28:17.290,0:28:24.370 that motion so for example if you press 0:28:20.950,0:28:25.990 the seek there's also this pattern that 0:28:24.370,0:28:27.880 if you press a particular editing key 0:28:25.990,0:28:30.400 twice it'll have that effect on the 0:28:27.880,0:28:32.980 given line so if I press D D that 0:28:30.400,0:28:34.360 deletes the line if I press C C that 0:28:32.980,0:28:35.560 deletes the given line but puts me in 0:28:34.360,0:28:39.760 insert mode so I can replace it with 0:28:35.560,0:28:43.360 some other line well cover a couple 0:28:39.760,0:28:44.290 other editing commands because then 0:28:43.360,0:28:46.720 later we'll see how all these things 0:28:44.290,0:28:48.700 interact together so another useful one 0:28:46.720,0:28:50.290 is the X command so suppose my cursor is 0:28:48.700,0:28:52.120 over some particular character you've 0:28:50.290,0:28:57.880 had pressed X it just deletes that 0:28:52.120,0:29:00.310 character there's another command called 0:28:57.880,0:29:02.260 R if I'm over a particular character and 0:29:00.310,0:29:03.940 I press R it takes another character as 0:29:02.260,0:29:05.440 an argument and it replaces that 0:29:03.940,0:29:12.550 particular character with some other 0:29:05.440,0:29:14.110 character and I'll cover a couple more 0:29:12.550,0:29:16.390 editing commands so I think when I 0:29:14.110,0:29:17.980 talked about a moment ago but of course 0:29:16.390,0:29:19.360 you can undo changes you've made in vim 0:29:17.980,0:29:21.520 and the way you do that is by pressing 0:29:19.360,0:29:23.230 you while your normal mode so you for 0:29:21.520,0:29:24.850 undo is pretty easy to remember so I 0:29:23.230,0:29:26.310 press you a whole bunch of times it's 0:29:24.850,0:29:28.750 undone all the changes I've made and 0:29:26.310,0:29:31.000 then the opposite of undos of course 0:29:28.750,0:29:40.960 redo and the binding for that in vim is 0:29:31.000,0:29:42.310 control are all right one other editing 0:29:40.960,0:29:55.090 command I'm going to talk about is copy 0:29:42.310,0:29:56.290 and paste because oh yes question that's 0:29:55.090,0:29:58.150 it that's a great question so the 0:29:56.290,0:29:59.500 question is does undo undo everything 0:29:58.150,0:30:00.970 you've done since you've gone into 0:29:59.500,0:30:02.380 insert mode or just the last character 0:30:00.970,0:30:03.280 it's it's actually a little bit more 0:30:02.380,0:30:05.860 complicated than that 0:30:03.280,0:30:07.540 undo does like undoes the last change 0:30:05.860,0:30:08.800 you've made so if you went into insert 0:30:07.540,0:30:10.480 mode and typed in some stuff and went 0:30:08.800,0:30:12.520 back into normal mode and then press you 0:30:10.480,0:30:14.560 for undo it'll undo all you've done in 0:30:12.520,0:30:16.090 insert mode but if you've done some 0:30:14.560,0:30:18.280 other type of editing command like say I 0:30:16.090,0:30:20.140 press X to delete a character if I do 0:30:18.280,0:30:24.280 you for undo it'll just undo that change 0:30:20.140,0:30:26.440 that that editing command made now does 0:30:24.280,0:30:28.780 that answer the question yeah great any 0:30:26.440,0:30:32.780 other questions 0:30:28.780,0:30:35.480 cool so I'll talk about copy and paste 0:30:32.780,0:30:37.580 as well because that's a popular one the 0:30:35.480,0:30:39.710 Y command stands for copying and the P 0:30:37.580,0:30:41.810 command stands for pasting y for coffee 0:30:39.710,0:30:43.370 because yank like that's the word date 0:30:41.810,0:30:46.310 that's the term logic terminology that 0:30:43.370,0:30:49.220 vim uses for copying and these commands 0:30:46.310,0:30:52.580 are y also takes a motion as an argument 0:30:49.220,0:30:54.350 so if I do like YY it copies the current 0:30:52.580,0:30:56.090 line in an effect press P for paste 0:30:54.350,0:30:57.260 notice that now these two lines are 0:30:56.090,0:31:00.110 identical because I've just pasted a 0:30:57.260,0:31:02.330 line below you for undo but if I do 0:31:00.110,0:31:04.910 something like YW it's copied the word 0:31:02.330,0:31:05.450 and then I can do P and it just pasted 0:31:04.910,0:31:08.930 that word again 0:31:05.450,0:31:10.700 right where my cursor was one useful 0:31:08.930,0:31:12.530 thing especially in the context of copy 0:31:10.700,0:31:14.150 and paste is to be able to select a 0:31:12.530,0:31:15.650 block of stuff and copy it right like 0:31:14.150,0:31:16.940 this is probably how to used copy and 0:31:15.650,0:31:19.220 paste in whatever editor you were using 0:31:16.940,0:31:21.440 before and so that's where we get into 0:31:19.220,0:31:23.210 the visual modes so these are another 0:31:21.440,0:31:24.590 set of modes that are all related to 0:31:23.210,0:31:26.030 each other and that can be reached from 0:31:24.590,0:31:28.790 normal mode and they're used for 0:31:26.030,0:31:31.040 selecting chunks of text so one mode is 0:31:28.790,0:31:33.140 just regular visual mode you can enter 0:31:31.040,0:31:34.820 that by pressing V and then once you're 0:31:33.140,0:31:36.650 in this mode you can use most of the 0:31:34.820,0:31:38.450 regular normal mode commands to move 0:31:36.650,0:31:39.980 your point around and it selects 0:31:38.450,0:31:42.050 everything in between so I can use like 0:31:39.980,0:31:44.030 hjkl just to move the cursor or I can 0:31:42.050,0:31:45.890 use W to move by words or different 0:31:44.030,0:31:48.080 things like that and it will select a 0:31:45.890,0:31:49.490 block of text and once I've selected 0:31:48.080,0:31:50.900 this block of text there a whole bunch 0:31:49.490,0:31:52.610 of different types of useful things you 0:31:50.900,0:31:54.770 could do with it one of the most popular 0:31:52.610,0:31:57.320 things to do is copying this so once 0:31:54.770,0:31:59.630 I've selected I can do Y to copy and it 0:31:57.320,0:32:01.280 puts me back into normal mode and now 0:31:59.630,0:32:02.810 it's copied this to the to the paste 0:32:01.280,0:32:04.850 buffer and then if I go somewhere else 0:32:02.810,0:32:07.670 and press P it pastes in that whole 0:32:04.850,0:32:10.520 chunk of text I copied and it's similar 0:32:07.670,0:32:13.610 to visual mode which selects kind of a 0:32:10.520,0:32:15.560 contiguous stream of text there's visual 0:32:13.610,0:32:17.720 line mode so that can be reached by 0:32:15.560,0:32:19.760 pressing capital V and that selects 0:32:17.720,0:32:21.470 whole lines at a time and then there's 0:32:19.760,0:32:23.150 visual block mode which can be selected 0:32:21.470,0:32:24.890 by pressing control V and that can 0:32:23.150,0:32:26.240 select rectangular blocks of text so 0:32:24.890,0:32:31.670 this is something your old editor 0:32:26.240,0:32:33.320 couldn't do alright so there's a lot 0:32:31.670,0:32:35.120 more vim editing commands to learn 0:32:33.320,0:32:36.710 there's lots of like really weird and 0:32:35.120,0:32:38.420 fancy things like for example the tilde 0:32:36.710,0:32:40.220 command changes the case of the 0:32:38.420,0:32:41.690 character or the selection that you've 0:32:40.220,0:32:43.640 currently selected so for 0:32:41.690,0:32:45.620 I can take this like Visual Studio code 0:32:43.640,0:32:48.260 and flick the case on the whole thing by 0:32:45.620,0:32:49.430 selecting it and pressing tilde and 0:32:48.260,0:32:50.480 there's a whole bunch of other things 0:32:49.430,0:32:52.160 like that they get more and more 0:32:50.480,0:32:54.050 esoteric as you go so we're not going to 0:32:52.160,0:32:56.630 cover all of those but you'll get to 0:32:54.050,0:32:58.490 those in the exercises so those are vim 0:32:56.630,0:33:00.620 editing commands and a lot of them can 0:32:58.490,0:33:02.120 be composed with movement commands so 0:33:00.620,0:33:09.260 any questions about either of those so 0:33:02.120,0:33:12.680 far cool so moving along another 0:33:09.260,0:33:14.240 category of things of commands that are 0:33:12.680,0:33:16.880 mostly relevant to normal mode are 0:33:14.240,0:33:18.530 counts so you can give them a number to 0:33:16.880,0:33:22.100 do a particular thing some number of 0:33:18.530,0:33:25.430 times so suppose my cursor is here and I 0:33:22.100,0:33:26.960 want to move down like 1 2 3 4 lines one 0:33:25.430,0:33:29.390 way I can do that is by pressing J four 0:33:26.960,0:33:32.570 times go down four times KK KK it goes 0:33:29.390,0:33:34.010 up four times but rather than pressing a 0:33:32.570,0:33:37.430 particular key again and again I can use 0:33:34.010,0:33:38.960 a count so if I press four J it does J 0:33:37.430,0:33:40.130 four times right 0:33:38.960,0:33:42.290 thumbs interface is a programming 0:33:40.130,0:33:45.890 language if I do four K it moves up four 0:33:42.290,0:33:47.600 times if I am here and I press me to go 0:33:45.890,0:33:49.040 into visual mode okay so now I can move 0:33:47.600,0:33:51.680 my cursor around and select blocks of 0:33:49.040,0:33:53.660 text I can do like EEE to select a 0:33:51.680,0:33:56.600 couple of words but I could also go back 0:33:53.660,0:33:59.720 here v for visual mode and press three E 0:33:56.600,0:34:03.080 to select like three ends of words for 0:33:59.720,0:34:05.060 word and then of course these can also 0:34:03.080,0:34:08.000 be combined with editing commands so 0:34:05.060,0:34:10.910 like suppose I want to delete seven 0:34:08.000,0:34:13.970 words I can do that by moving my cursor 0:34:10.910,0:34:17.660 somewhere and doing seven dw7 delete 0:34:13.970,0:34:19.490 words and so this is particularly useful 0:34:17.660,0:34:21.260 for things like suppose my cursor 0:34:19.490,0:34:22.460 somewhere on the screen and I'm looking 0:34:21.260,0:34:24.020 somewhere else on the screen or I want 0:34:22.460,0:34:26.240 my cursor to go to that particular line 0:34:24.020,0:34:28.400 notice that I've set up relative line 0:34:26.240,0:34:29.750 numbering on the left so wherever my 0:34:28.400,0:34:31.580 cursor is it shows the current line 0:34:29.750,0:34:33.830 number but everywhere else it's just the 0:34:31.580,0:34:35.870 offset from where I am now suppose my 0:34:33.830,0:34:38.480 cursor is here but I want to move down 0:34:35.870,0:34:40.160 to the like Microsoft Word down here so 0:34:38.480,0:34:41.810 that's eight lines down so what 0:34:40.160,0:34:44.020 combination of keys would I press to do 0:34:41.810,0:34:45.560 that like what's the most efficient way 0:34:44.020,0:34:47.810 yeah exactly 0:34:45.560,0:34:50.440 let's try that out 8j and my cursor move 0:34:47.810,0:34:50.440 down to this line 0:34:51.270,0:34:57.880 okay and then one final category of key 0:34:56.110,0:34:59.920 meanings in BIM is something called 0:34:57.880,0:35:02.200 modifier so we have so far movement 0:34:59.920,0:35:04.900 edits counts and finally we have 0:35:02.200,0:35:06.520 modifiers so modifiers kind of change 0:35:04.900,0:35:08.830 the meaning of a movement command a 0:35:06.520,0:35:11.530 little bit and a couple modifiers that 0:35:08.830,0:35:15.190 are especially useful are the 8 and I 0:35:11.530,0:35:18.010 modifier so a stands for like around and 0:35:15.190,0:35:19.900 I stands for inside and to see where 0:35:18.010,0:35:21.760 this is really useful I can move my 0:35:19.900,0:35:22.480 cursor to somewhere like here for 0:35:21.760,0:35:24.670 example 0:35:22.480,0:35:26.320 so hopefully most of you are familiar 0:35:24.670,0:35:28.240 with markdown syntax and if not it 0:35:26.320,0:35:30.490 doesn't matter too much this is a 0:35:28.240,0:35:31.780 Lincoln markdown it's a text rendered in 0:35:30.490,0:35:33.610 square brackets and then the link in 0:35:31.780,0:35:35.500 parentheses suppose my cursor is inside 0:35:33.610,0:35:38.350 here and I want to change the text 0:35:35.500,0:35:40.150 corresponding to this link well one way 0:35:38.350,0:35:43.480 I could do that is like move back here 0:35:40.150,0:35:45.130 with B and like to DW and then I to go 0:35:43.480,0:35:46.450 into insert mode like that's one of the 0:35:45.130,0:35:47.950 many ways I can make this change and I 0:35:46.450,0:35:51.070 can type in whatever other thing I want 0:35:47.950,0:35:53.410 you to undo huge undo another way could 0:35:51.070,0:35:58.030 have done that is change two words C to 0:35:53.410,0:35:59.950 W and then type in some other text but 0:35:58.030,0:36:03.280 one final way I could do the same change 0:35:59.950,0:36:05.380 is using the modifier commands to talk 0:36:03.280,0:36:07.120 about how I want to interact with these 0:36:05.380,0:36:09.490 different types of grouping things like 0:36:07.120,0:36:12.070 parentheses and square brackets so one 0:36:09.490,0:36:15.610 final way of doing this is change inside 0:36:12.070,0:36:17.440 square brackets CI bracket and that puts 0:36:15.610,0:36:20.230 me into insert mode after deleting the 0:36:17.440,0:36:21.400 contents that are inside the brackets so 0:36:20.230,0:36:22.690 do you see how we can take all these 0:36:21.400,0:36:24.310 different ingredients like we talked 0:36:22.690,0:36:25.570 about change and we could combine that 0:36:24.310,0:36:27.460 with different movement commands we 0:36:25.570,0:36:30.100 talked about inside how it's a modifier 0:36:27.460,0:36:32.770 and then we talked about X we didn't 0:36:30.100,0:36:34.230 talk about parentheses but if your 0:36:32.770,0:36:36.070 cursor is hovering over a different 0:36:34.230,0:36:37.810 different types of grouping things like 0:36:36.070,0:36:39.880 parentheses or square brackets you can 0:36:37.810,0:36:40.990 press the percent movement key to jump 0:36:39.880,0:36:45.340 back and forth between matching 0:36:40.990,0:36:49.510 parentheses if I go over here and I do D 0:36:45.340,0:36:52.480 I parentheses I can delete the contents 0:36:49.510,0:36:55.780 inside these parentheses and so those 0:36:52.480,0:36:57.550 are vim modifiers I guess we talked 0:36:55.780,0:37:00.310 about I but we didn't talk about a if I 0:36:57.550,0:37:02.080 do D a parenthesis it deletes a whole 0:37:00.310,0:37:04.460 like parenthesized group including the 0:37:02.080,0:37:10.730 parentheses so I is inside 0:37:04.460,0:37:11.839 is around or including all right so 0:37:10.730,0:37:13.670 those are basically the different 0:37:11.839,0:37:15.890 categories of things you can combine 0:37:13.670,0:37:18.050 together when interacting with VIMS 0:37:15.890,0:37:20.330 interface so any questions about that or 0:37:18.050,0:37:28.820 the overall idea of this interface being 0:37:20.330,0:37:31.580 a programming language cool so let's do 0:37:28.820,0:37:33.859 a quick demo to kind of demonstrate the 0:37:31.580,0:37:36.290 power of this editor and it will kind of 0:37:33.859,0:37:38.240 help us see how this tool can work 0:37:36.290,0:37:41.260 really fast and kind of match the speed 0:37:38.240,0:37:43.760 at which we think so over here is a very 0:37:41.260,0:37:44.780 broken fizzbuzz implementation that 0:37:43.760,0:37:46.640 doesn't actually print anything 0:37:44.780,0:37:48.680 hopefully most of you have heard of 0:37:46.640,0:37:51.080 fizzbuzz if not I'll explain it super 0:37:48.680,0:37:52.730 briefly this buzz is a programming 0:37:51.080,0:37:54.290 exercise where you print the numbers 1 0:37:52.730,0:37:56.540 through n but when the number is 0:37:54.290,0:37:58.700 divisible by 3 you print fizz when it's 0:37:56.540,0:38:00.859 divisible by 5 you print buzz and when 0:37:58.700,0:38:02.839 it's divisible by both 3 & 5 you print 0:38:00.859,0:38:05.089 fizzbuzz and if none of those apply you 0:38:02.839,0:38:09.290 just print the number so you should 0:38:05.089,0:38:13.460 print like 1 2 fizz for buzz and so on 0:38:09.290,0:38:16.550 but if I run this program it doesn't 0:38:13.460,0:38:20.089 print anything here I have them on the 0:38:16.550,0:38:21.530 left in just a terminal on the right ok 0:38:20.089,0:38:23.750 so there's a bunch of issues with this 0:38:21.530,0:38:26.470 one is that main is never called so 0:38:23.750,0:38:29.450 let's start off with fixing that so 0:38:26.470,0:38:31.960 here's how I would make this change and 0:38:29.450,0:38:34.250 notice how few keystrokes this requires 0:38:31.960,0:38:37.609 capital G means go to the bottom of the 0:38:34.250,0:38:39.650 file o opens a new line below and now I 0:38:37.609,0:38:45.380 can just type in stuff so I'm an insert 0:38:39.650,0:38:47.210 mode okay so I've typed in whatever 0:38:45.380,0:38:50.480 change I want to make escape to go back 0:38:47.210,0:38:53.540 to normal mode if I do : W so command 0:38:50.480,0:38:54.650 mode right let me go back here okay now 0:38:53.540,0:38:56.690 at least my program prints something 0:38:54.650,0:38:58.940 when I run it another issue with this 0:38:56.690,0:39:02.750 program is that it starts at 0 instead 0:38:58.940,0:39:05.030 of 1 so let's go fix that so I want to 0:39:02.750,0:39:06.950 go over to this range whoops this range 0:39:05.030,0:39:08.480 thing and it shouldn't be going from 0 0:39:06.950,0:39:11.270 to limit it should be going from 1 to 0:39:08.480,0:39:12.650 limit plus 1 1 command which I didn't 0:39:11.270,0:39:16.060 show you about is how you search in vim 0:39:12.650,0:39:16.060 so you press forward slash 0:39:17.010,0:39:21.930 to close this and restart it if you 0:39:19.080,0:39:24.840 press forward slash it starts search so 0:39:21.930,0:39:26.220 if I type in range enter my cursor goes 0:39:24.840,0:39:27.810 from wherever it was before to the first 0:39:26.220,0:39:28.920 instance of range it found so it's a 0:39:27.810,0:39:31.680 really efficient way of moving where I 0:39:28.920,0:39:33.990 want to move WW to move forward two 0:39:31.680,0:39:36.330 words I to go into insert mode add the 0:39:33.990,0:39:38.310 one comma space escape I'm back in 0:39:36.330,0:39:40.080 normal mode this is a very common 0:39:38.310,0:39:41.850 pattern in vim you stay in normal mode 0:39:40.080,0:39:43.260 you go somewhere you go into insert mode 0:39:41.850,0:39:44.880 you make a tiny change and you jump 0:39:43.260,0:39:45.900 right back to normal mode like normal 0:39:44.880,0:39:48.810 mode is home and that's where you should 0:39:45.900,0:39:51.030 be most of the time I also want to add a 0:39:48.810,0:39:55.430 plus one so e to go to the end of this 0:39:51.030,0:39:58.140 word a for a pend plus one escape 0:39:55.430,0:40:00.810 alright fix that problem and other issue 0:39:58.140,0:40:02.940 is that this program prints fizz for 0:40:00.810,0:40:05.970 both divisible by three and five so 0:40:02.940,0:40:07.920 let's fix that slash fizz searches for 0:40:05.970,0:40:11.790 fizz been oppressed and it goes to the 0:40:07.920,0:40:13.710 next match see I press E I quote changes 0:40:11.790,0:40:15.660 what's inside the quote so it's deleted 0:40:13.710,0:40:17.460 the fizz and put me in insert mode right 0:40:15.660,0:40:18.510 in between those two quotes and I can 0:40:17.460,0:40:23.460 type in whatever I want 0:40:18.510,0:40:26.630 escape to go back to normal mode so 0:40:23.460,0:40:28.890 great I've fixed that particular problem 0:40:26.630,0:40:31.710 another problem with this program is 0:40:28.890,0:40:37.710 that it prints fizz and Buzz on separate 0:40:31.710,0:40:42.150 lines for multiples of 15 so let's let's 0:40:37.710,0:40:42.870 go and fix that let me go down to this 0:40:42.150,0:40:44.580 line here 0:40:42.870,0:40:46.350 one way I can don't actually worry about 0:40:44.580,0:40:47.430 like the actual contents of this program 0:40:46.350,0:40:48.690 like this some stupid program that 0:40:47.430,0:40:51.000 doesn't matter pay attention to what 0:40:48.690,0:40:52.170 keys I'm pressing in vim that allow me 0:40:51.000,0:40:54.960 to make changes to this program really 0:40:52.170,0:40:56.790 efficiently so my cursor is on this line 0:40:54.960,0:40:59.460 i press dollar to go to the end of this 0:40:56.790,0:41:01.170 line i for insert mode okay and i'm 0:40:59.460,0:41:03.330 typing some stuff escape to go back to 0:41:01.170,0:41:07.050 normal mode now I want to make the same 0:41:03.330,0:41:11.610 change the print below look at this JJ 0:41:07.050,0:41:13.260 dot so what dot dozen vim is it repeats 0:41:11.610,0:41:15.990 the previous editing command that was 0:41:13.260,0:41:17.880 made and so this is a really nice way of 0:41:15.990,0:41:19.890 doing repetitive tasks without typing 0:41:17.880,0:41:21.630 the same thing over and over again so in 0:41:19.890,0:41:24.630 that particular case that inserted comma 0:41:21.630,0:41:27.110 end quote and so it applied the same 0:41:24.630,0:41:29.580 thing on this line when I press dot and 0:41:27.110,0:41:30.690 then when I guess one final part of this 0:41:29.580,0:41:32.930 demo is 0:41:30.690,0:41:34.620 we will fix the issue that this program 0:41:32.930,0:41:35.670 maybe should take a command-line 0:41:34.620,0:41:38.520 argument instead of having this 0:41:35.670,0:41:40.440 hard-coded 10 down here so how do we do 0:41:38.520,0:41:43.170 that I'll press GG to go to the top 0:41:40.440,0:41:44.490 capital o so now I've opened a line 0:41:43.170,0:41:47.220 above and I'm going to type in some text 0:41:44.490,0:41:49.710 like imports this enter escape to go 0:41:47.220,0:41:52.110 back to normal mode and then I want to 0:41:49.710,0:41:54.870 go down to where this 10 is so slash 10 0:41:52.110,0:41:57.540 makes me jump straight down there CI 0:41:54.870,0:41:59.760 pren to edit what's inside the 0:41:57.540,0:42:02.150 parentheses and now I can type in like 0:41:59.760,0:42:07.080 whatever thing I need to type in here 0:42:02.150,0:42:09.840 and then once I've done this my program 0:42:07.080,0:42:10.920 does fizzbuzz correctly I think I missed 0:42:09.840,0:42:12.390 one change I wanted to make but it 0:42:10.920,0:42:14.540 doesn't matter this demonstrates that 0:42:12.390,0:42:17.250 you can make lots of changes really fast 0:42:14.540,0:42:23.400 so any questions about this demo or the 0:42:17.250,0:42:27.960 overall idea we've been talking about ok 0:42:23.400,0:42:29.550 so this will be covered Tuesday so the 0:42:27.960,0:42:31.710 kind of outside environment I'm running 0:42:29.550,0:42:33.630 vim on the left and my shell on the 0:42:31.710,0:42:38.910 right and then this is team ox on the 0:42:33.630,0:42:39.900 outside one variant of that question 0:42:38.910,0:42:41.670 might be like how do you switch between 0:42:39.900,0:42:42.840 different vim windows and you can see 0:42:41.670,0:42:44.250 the lecture notes for that but there's a 0:42:42.840,0:42:45.720 key binding for that so if you have the 0:42:44.250,0:42:50.240 same window open or multiple things open 0:42:45.720,0:42:50.240 there's a way of doing that question ah 0:42:50.840,0:42:56.520 good question so delete takes a motion 0:42:54.570,0:42:58.110 and then removes those contents but 0:42:56.520,0:43:00.120 keeps you in normal mode so you can keep 0:42:58.110,0:43:02.430 just moving around in a file what change 0:43:00.120,0:43:03.900 does is very similar to delete it takes 0:43:02.430,0:43:06.150 motions and treats them in the same way 0:43:03.900,0:43:07.980 deletes those contents but then puts you 0:43:06.150,0:43:11.280 in insert mode and so it saves you from 0:43:07.980,0:43:13.290 typing one extra keystroke so if I'm 0:43:11.280,0:43:16.380 here for example I want to delete main 0:43:13.290,0:43:18.240 DW deletes a word but now if I press 0:43:16.380,0:43:21.720 whatever key likes I press J it just 0:43:18.240,0:43:23.490 moved me down if I undo that do cw4 0:43:21.720,0:43:24.810 change a word now it's actually put me 0:43:23.490,0:43:28.640 into insert mode and I can type in 0:43:24.810,0:43:31.890 whatever I want it to insert so DWI is 0:43:28.640,0:43:33.810 the same thing as CW but it saves a 0:43:31.890,0:43:35.280 keystroke one thing we've linked in the 0:43:33.810,0:43:37.140 resources is something called vim golf 0:43:35.280,0:43:39.840 basically people have set up a game 0:43:37.140,0:43:41.400 online where you can get an editing task 0:43:39.840,0:43:43.590 and try to figure out the minimal number 0:43:41.400,0:43:44.490 of keystrokes necessary to complete that 0:43:43.590,0:43:46.020 editing 0:43:44.490,0:43:47.340 it's actually really addictive so I'd 0:43:46.020,0:43:52.680 only suggest going on their chest and 0:43:47.340,0:44:00.450 script time I think I saw a hand for 0:43:52.680,0:44:02.070 another question yeah uh period yeah one 0:44:00.450,0:44:05.750 of the most useful of em commands good 0:44:02.070,0:44:05.750 question any other questions 0:44:06.740,0:44:13.260 cool so I think we have about five 0:44:10.800,0:44:14.760 minutes left and I'm gonna briefly talk 0:44:13.260,0:44:15.990 about a thing that's also covered in 0:44:14.760,0:44:19.470 detail in the notes so make sure you 0:44:15.990,0:44:22.349 look at the notes for this so vim is a 0:44:19.470,0:44:24.420 programmers text editor and so of course 0:44:22.349,0:44:25.740 it's highly programmable not only 0:44:24.420,0:44:27.720 through its interface that's a 0:44:25.740,0:44:29.099 programming language but also a couple 0:44:27.720,0:44:31.050 of different ways there's lots of 0:44:29.099,0:44:32.970 settings that you can tweak to match 0:44:31.050,0:44:34.740 your preferences and you can also 0:44:32.970,0:44:37.590 install plugins for them that do all 0:44:34.740,0:44:40.380 sorts of useful stuff so the way vim is 0:44:37.590,0:44:42.930 configured is through a file on disk 0:44:40.380,0:44:45.480 called vim RC and you'll see this is a 0:44:42.930,0:44:47.340 common pattern in a lot of shell based 0:44:45.480,0:44:49.349 tools there'll be a plain text file that 0:44:47.340,0:44:50.880 configures how the Tool Works and so if 0:44:49.349,0:44:53.670 I edit this file and it may or may not 0:44:50.880,0:44:56.310 exist on your machine yet but I've 0:44:53.670,0:44:58.170 downloaded the we've created a kind of 0:44:56.310,0:44:59.430 default vim RC for you and linked it on 0:44:58.170,0:45:02.190 the course website so you can start with 0:44:59.430,0:45:04.859 that one if I do vim tilde slash boom RC 0:45:02.190,0:45:07.080 I can see here a bunch of comments and 0:45:04.859,0:45:09.060 then particular commands like by default 0:45:07.080,0:45:11.280 we want syntax highlighting on and we 0:45:09.060,0:45:12.750 want line numbers if we didn't do some 0:45:11.280,0:45:14.880 of these things like let me remove the 0:45:12.750,0:45:16.500 stuff that sets line numbers if I remove 0:45:14.880,0:45:17.790 those configurations and relaunch vim 0:45:16.500,0:45:21.270 notice that I no longer have line 0:45:17.790,0:45:23.099 numbers on the left but yeah so in short 0:45:21.270,0:45:26.099 there's a lot of stuff you can configure 0:45:23.099,0:45:28.589 with them we've given you a very basic 0:45:26.099,0:45:29.880 configuration that tries to like remove 0:45:28.589,0:45:32.160 some of the kind of weird behavior 0:45:29.880,0:45:33.480 that's on by default in vim but we don't 0:45:32.160,0:45:35.550 really try to enforce too many of our 0:45:33.480,0:45:37.080 other opinions on you but of course like 0:45:35.550,0:45:39.210 the three of us used them a lot and we 0:45:37.080,0:45:41.310 have heavily customized VMR C's so we've 0:45:39.210,0:45:42.480 linked to our personal configurations 0:45:41.310,0:45:44.550 too if you want to take anything from 0:45:42.480,0:45:46.050 that and also like thousands or like 0:45:44.550,0:45:47.640 millions of people share their var C's 0:45:46.050,0:45:48.450 on github so there's lots of places to 0:45:47.640,0:45:49.920 look for inspiration 0:45:48.450,0:45:53.040 there's also cool blog posts on this 0:45:49.920,0:45:54.810 topic another thing you can do in vim is 0:45:53.040,0:45:56.820 you can extend it with plugins that do 0:45:54.810,0:45:58.080 all sorts of useful things this lets you 0:45:56.820,0:45:59.730 do things like fuzzy file 0:45:58.080,0:46:00.960 finding which a lot of text editors come 0:45:59.730,0:46:02.790 with by default so you can get like a 0:46:00.960,0:46:04.710 pop-up window you can type in a name of 0:46:02.790,0:46:07.020 a file or approximately the name of a 0:46:04.710,0:46:08.480 file and find it very quickly or there 0:46:07.020,0:46:10.920 are things that show you like 0:46:08.480,0:46:14.970 visualizations of undo history there are 0:46:10.920,0:46:16.350 things that show you like file explorers 0:46:14.970,0:46:18.360 things like that so we've linked to a 0:46:16.350,0:46:20.520 couple of our favorite plugins on the 0:46:18.360,0:46:22.230 course website and so I highly recommend 0:46:20.520,0:46:23.340 becoming familiar with how to install a 0:46:22.230,0:46:24.840 plug-in because it takes like three 0:46:23.340,0:46:29.580 seconds and some of them are really cool 0:46:24.840,0:46:32.130 and then finally the last topic I'll 0:46:29.580,0:46:34.680 briefly mention before we finish today's 0:46:32.130,0:46:37.170 lecture is vim mode and other programs 0:46:34.680,0:46:38.760 so turns out that a lot of programmers 0:46:37.170,0:46:40.650 we're really excited about VIMS 0:46:38.760,0:46:42.780 interface and so they've implemented 0:46:40.650,0:46:44.730 similar functionality and other tools 0:46:42.780,0:46:47.730 for example like I've configured my 0:46:44.730,0:46:49.530 Python repple to run in vim mode so I 0:46:47.730,0:46:51.720 can like type in stuff here and if I 0:46:49.530,0:46:53.250 press escape now I'm in normal mode in 0:46:51.720,0:46:55.230 my Python repple and I can like move 0:46:53.250,0:46:58.190 back and forth and like press X here 0:46:55.230,0:47:01.530 delete a thing like CW change a word and 0:46:58.190,0:47:03.210 do all those good things and it's not 0:47:01.530,0:47:05.910 just the Python repple like I have my 0:47:03.210,0:47:07.890 terminal behaving this way too so like I 0:47:05.910,0:47:10.050 can type in whatever I want here and 0:47:07.890,0:47:11.430 like escape and I'm in normal mode I can 0:47:10.050,0:47:13.320 go here and like go into visual mode 0:47:11.430,0:47:15.570 inside my terminal and like select 0:47:13.320,0:47:19.680 blocks of text press tilde to change the 0:47:15.570,0:47:22.080 case whatever so we've linked sir like 0:47:19.680,0:47:25.800 how exactly you can enable vim mode for 0:47:22.080,0:47:27.510 like bash z shell fish a lot of read 0:47:25.800,0:47:28.710 line based programs like jupiter 0:47:27.510,0:47:30.330 notebook a whole bunch of other things 0:47:28.710,0:47:32.130 and if it's not another place you can 0:47:30.330,0:47:33.840 probably find it by googling it because 0:47:32.130,0:47:36.030 a lot of people like to have this sort 0:47:33.840,0:47:37.380 of functionality and if you're really 0:47:36.030,0:47:39.270 gonna like commit to learning them I 0:47:37.380,0:47:41.490 think it's valuable to enable this sort 0:47:39.270,0:47:43.080 of like vim emulation mode in every tool 0:47:41.490,0:47:44.970 you use is like one or like make you 0:47:43.080,0:47:46.800 learn the tool a lot better and to once 0:47:44.970,0:47:47.970 you become good at vim like those skills 0:47:46.800,0:47:53.130 will now transfer to all your other 0:47:47.970,0:47:54.840 tools you use okay so I think that's it 0:47:53.130,0:47:57.060 for our rapid introduction to them 0:47:54.840,0:47:58.320 there's some other neat material that we 0:47:57.060,0:47:59.790 weren't able to fit in today's lecture 0:47:58.320,0:48:01.140 but it's in the lecture notes and then 0:47:59.790,0:48:02.880 finally I highly recommend going through 0:48:01.140,0:48:05.220 the exercises for today like at least 0:48:02.880,0:48:07.440 for me personally I think spending time 0:48:05.220,0:48:08.910 learning my text editor has been like 0:48:07.440,0:48:10.140 the most beneficial thing out of like 0:48:08.910,0:48:11.580 the kinds of things we're teaching in 0:48:10.140,0:48:14.020 this class 0:48:11.580,0:48:15.540 so yeah that's it for today's lecture 0:48:14.020,0:48:17.530 and we'll see you tomorrow 0:48:15.540,0:48:20.320 note that we've changed tomorrow's 0:48:17.530,0:48:22.060 lecture to data wrangling Thursday and 0:48:20.320,0:48:23.500 Tuesday lectures are now switched this 0:48:22.060,0:48:25.000 is reflected on the course website in 0:48:23.500,0:48:27.510 case anybody was going to come to one 0:48:25.000,0:48:27.510 but not the other