Vim.md

Vim and Markdown

Vim

Vim is described as a 'highly configurable text editor for efficiently creating and changing any kind of text'.

Vim is included under the alias vi on most UNIX systems, as well as OS X.

Vim is designed with the intent to have functions easily accessible and to never require the user to remove their hands from the home row.

Getting started with Vim

To start Vim without opening a specific file simply type vim on the terminal. To open a file, write vim filename, in the case of this file, one would type vim Vim.md, like you likely already have.

To quit Vim, simply hit esc a couple of times, then type :q and hit enter. Hitting escape ensures that you are not in insert mode. If this gives you an error, typing :q! will force exit, but will discard all changes.

To save a file in Vim, hit escape and type :w this will save the file directly back to the same filename. This can be combined with the q command with :wq, saving and quitting at the same time.

Modes of Vim

Before we jump into movement, we should quickly go over 3 modes of Vim; normal, insert and visual. You can enter these modes at any time while not in another mode, and can get out of them by hitting the esc key.

Normal

Normal mode is the default mode of Vim, and the mode Vim goes to when the escape key is pressed. In this mode, you can freely move the cursor, do some limited text manipulation, enter commands, search, and enter the other two modes.

Any Vim command that is not a simple keypress will start with a : and is written to the bottom of the terminal.

Insert

While in insert mode, Vim acts as a basic text editor, type on the keyboard and text appears in the file. Cursor movement can be achieved with the arrow keys. Insert mode can be accessed with the i key, and will start the insertion at the exact character that the cursor is on. If you wish to start at the character after, use the a key instead

• i enter insert mode at current character
• a enter insert mode after current character

Visual

Visual mode is akin to selecting text in a graphical editor, though with some more features. For now, enter visual mode with v selecting the current character, and move the cursor to select more text.

• v enter visual mode on a character-by-character basis
• V enter visual mode on a line-by-line basis

This mode acts like the copy-paste mode of Vim.

Some commands from normal mode can actually be done in visual mode, and if those commands take a selection of text as an argument, the selection will automatically be whatever is selected. This allows for a simple 'replace in selection function.'

Basic movement

Moving Vim's cursor can be accomplished with the arrow keys, in a way similar to that of 'normal' text editors, or with the use of the h j k and l keys

• h moves the cursor left
• j moves the cursor down
• k moves the cursor up
• l moves the cursor right

Some more complicated movement can be achieved with other keys

• w jump one word ahead
• b jump one word backwards
• 0 start of line
• ^ first non-blank character of line
• $ end of line
• ctrl+d move one-half page down
• ctrl+u move one-half page up
• gg top of page
• G bottom of page

Many of these advanced options can be combined with the v visual mode to select quicker, such as v$ selects all text from the current character to the end of the line.

Advanced movement will be described more later.

Getting more advanced

Something to remember while using Vim, if you want to do some simple changes to text or movement in Vim, there's a good chance that it exists, and you should check online to see what the command is.

I'll also point to my vimrc where I have a fairly barebones config that makes the most of default Vim options. I have added quite a bit to my Vim config over the past year. However, most things that are not basic Vim functions look more complicated, and should be fairly simple to breeze over. Most everything is commented and if you can't figure something out feel free to ask me.

A vimrc is basically a configuration file for Vim. It contains basic Vim functions that are called every time Vim is started, instead of needing to run them all manually.

Useful features

Some useful features that are not enabled by default on vim are line numbers and syntax highlighting (if not enabled by default). These can be enabled with :set number, and :set syn. These can also be added to the vimrc when you get more comfortable and are ready to set that up.

Simple macros

The c key while in normal mode will allow you to delete a selection and immediately start inserting text, c stands for change after all. Though c on its own will wait for a secondary input to tell it what it is removing. Using keys from the more complicated movement section we can do commands like:

• cw change word: delete until the next space character, and insert
• c$ delete until the end of the line, and begin inserting

A similar command is the d key, for delete. This, like change, will wait for a secondary command before doing anything, though this has one useful combination specifically for deleting: dd which will delete an entire line.

Both of these commands can be issued in visual mode, and will do with one keystroke the action it intended to do, such as selecting a couple of words and hitting c will immediately take you to insert where that text was.

Undo and redo in Vim are used by u and ctrl+r respectively, and . can repeat the last used command.

Cut/paste

The visual mode is mostly used for cutting and pasting, however Vim does not share the same clipboard as the rest of the system. (at least by default)

In visual mode, when you have a selection of text, these are the commands:

• d cuts the selection of text. Note that this has the same behavior whenever text is mass-deleted even while not in visual mode, it is saved to the text buffer.
• y is copy, or yank in Vim's case.
• p is paste. This can be done over a selection of text in the same way as anywhere else in the system.

Note that p can be used anytime not in insert mode.

Find

The last part of Vim I will go over in this document is the find tool, it works like it does in any other text editor but it is accessed with a simple / this is then followed by any text you want to search for. You can then page through all results using n and N to go forwards and backwards respectively.

Find/replace

Vim's substitute command isn't as easy as some other text editors, but with some practice it isn't that bad.

The basic syntax is :s/<find>/<replace>. Writing the command like this will only replace the first instance of <find> on the current line your cursor is on though. Hardly useful. Lets take a look at a few expansions, replacing foo and bar:

:%s/foo/bar " replace the first instance of foo on each line with bar
:%s/foo/bar/g " replace every instance of foo with bar
:5,12s/foo/bar/g " replace every foo with bar in lines 5-12

This is another one of those commands that can be used with the visual tool, so if you enter visual mode and begin selecting, then type :, you will notice that :'<,'> is populated automatically, this means that Vim is going to use the text selected already for the range of the next action. We can then use :'<,'>s/foo/bar/g to do a find and replace in selection.

See? Not so bad.

Visual block

One thing I want to mention but don't have a good place to is the visual block mode. It is useful sometimes and something you might not find out about for a while unless someone tells you so I'll just bring it up here.

Say, for instance you have a couple of lines with similar text and you want to do a bulk insert in the middle of the line. While you could do a small vimscript to do this, I don't know how to write vimscript. So the solution I use is the visual block mode.

Hitting ctrl+v whisks you away to the strange world of visual block mode. In this mode you can do what it sounds like: select blocks of text instead of lines.

Visual block mode works basically like regular visual mode with some minute differences:

• You can simply enter insert mode from this mode, but you must use I or similar instead of regular i. I have no clue why.
• Any action you do on one line will be replicated across all selected ones.
• Text won't look like it's being inserted on every line, but it will be when you exit insert mode.

Finally

Vim is a very powerful text editing tool, and if you get used to it you will never want to go back to anything less. There are great resources out there for commands and shortcuts, the one I've been using for writing this guide is Vimsheet.com. There are many plugins for Vim but I wouldn't really recommend any until you are comfortable with the basic features of Vim and understand what you need.

Markdown

Before this starts, if you are on a Linux/Mac distribution and you want to see this code update live you can go install grip to view this markdown file on your system.

From here out, I'll be leaving everything improperly formatted for markdown as practice using both it and Vim.

--- Basics of markdown ---

Markdown is described on the wiki page as a 'lightweight markup language with plain text formatting syntax.' As far as we're concerned, markdown is a useful tool for quickly writing code documentation, readmes for github, and converting to HTML.

A lot of markdown's features are above, so we will touch base on a lot of those things but mostly go over things I haven't used yet.

Headers use the # to denote the level of header. The more #s the smaller the header. header 1 header 2 header 3

Paragraphs are unformatted, but to start a new paragraph, two newlines are required (you can also use two spaces at the end of the line, but this is less readable). Links can be internal and external, and are created with brackets of the text to be displayed followed by parenthesis of the link. Images can be linked in same way with an explination point in front. Something like

When documenting code, it's very useful to have examples in the documentation. Thankfully, showing code is very simple;

Characters that markdown would normally read as syntax must be escaped with the \ character, but the \ character itself need not be.

inline code is denoted by surrounding it with ` characters (the one below the escape key)

Block code is denoted by three ` characters, and syntax highlighting works by putting the code type on the first line.

//code//java if(bool.toString().equals("true")) { return 1 == 1; } //code//

The last few things that markdown does are numbered and bulleted lists 1 numbered lists start with 1. But any number after doesn't matter 2 this will show up as 2 2 this will show up as 3 8325 this will show up as 4

Bulleted lists can start with a - or a *

Extra Vim stuff

Just some nice plugins that I have started using. None of these change Vim's behavior by very much, just add some nice features:

Vim-gitgutter is basically a column that tells you what has been added, removed, or modified in the current git tree. Nothing game-changing, but can be nice.

Vim-closer is a simple plugin to automagically close your brackets, parenthesis, and similar characters when you might forget. Very useful for javascript.

NERDTree is a replacement for the default Vim directory navigation, with some added niceties. The major ones are color coding of files based on type, option to pop-out NERDTree to the side of your current window, and git integration with nerdtree-git

Again, would hold off on these until you are used to Vim's basic functionality.