Editors

We already looked at nano to edit files. An editor not only allows us to write our source code, but it can also help us by:

  • Doing syntax highlighting of the language

  • Handle indentation for us

  • Show mismatched ) and } in our code

  • Autocompleting variable and function names

and more.

Let’s look at some common editors

xkcd comic on editors

Fig. 6 from XKCD

nano

nano is a pretty basic editor and very easy to use. We already saw that when we saved our hello.cpp it recognized it as C++ code and highlighted it in different colors.

There are some basic customizations you can make by creating a ~/.nanorc file, some of which are listed here: customizing nano

You will be able to complete all of the course work using nano as your editor. However you are encouraged to explore alternatives.

emacs

Emacs is a powerful editor that has a large number of extensions.

You can run emacs in a terminal (instead of a separate window), by doing:

emacs -nw

This is useful for remote connections.

Some basic commands with emacs:

  • C-x C-c : exit without saving

  • C-x C-s : save the file

  • C-g : break out of whatever command you may be in the middle of

  • C-space : set a mark (starting point) for selecting text

  • C-w : cut the text (into the “kill ring”)

  • C-y : paste the text from the kill ring (y is for yank)

Here C- means use the control key.

Here’s my emacs config file file.

vim/vi

vi or vim has two modes: command mode where you enter commands like save, delete, cut / paste, etc. and insert mode where you enter text into the editor.

You can open a file for editing by:

vi file.txt

by default you are in command mode.

  • To get into insert type i

  • To return to comamnd mode hit the ESC key

Documentation is available here: https://www.vim.org/docs.php

To save the file and exit you enter command mode and type :wq

VS Code

VS Code is a graphical editor that is extremely popular today. It has a large number of extensions. One of the most popular extensions is the “remote - ssh” extension that allows you to run VS Code on your local machine and edit files on a remote machine (connecting via SSH).

There are extensive introductory videos here: https://code.visualstudio.com/docs/introvideos/basics