Editor
Programming Environment
COP-3402
Table of Contents
Multiplexer-based development workflow
ssh NID@eustis.cecs.ucf.edu mkdir hello cd hello/ byobu emacs hello.c # press F2 for new byobu window gcc -o hello hello.c # notice bug # F3 to switch back to editor # F4 to switch back to compiler gcc -o hello hello.c ./hello # F6 to detach # byobu to reattach, selecting session number
Emacs
Overview
Emacs is a text-editor, designed to be
- Self-documenting (Ctrl-h for help)
- Customizable (change keybindings)
- Extensible (write packages)
More than text editing
- Invoke sub-processes (make, terminal, etc.)
- Email, IRC, etc.
- git integration
- File management and viewing
- Windowing
- org-mode (this class's webpage!)
Alt-X tetris
Tutorial
After logging into eustis, run
emacs -f help-with-tutorial
| Keyboard | Mnemonic | Description |
|---|---|---|
| Ctrl-X Ctrl-C | Ctrl-C kills processes in bash | Exit emacs |
Easy cursor movement
Can use keyboard navigation keys
- Up, down, left, right
- Pg-up, Pg-down
- Home, end
Warning: cannot use the mouse when in terminal only, though emacs does have mouse support in windowed versions.
The emacs way
| Keyboard | Mnemonic | Description |
|---|---|---|
| Ctrl-p or <up> | p for previous | Previous line |
| Ctrl-n or <down> | n for next | Next line |
| Ctrl-f or <right> | f for forward | Forward a character |
| Ctrl-b or <left> | b for backward | Backward a character |
| Ctrl-a or <home> | a is beginning of the alphabet | Beginning of line |
| Ctrl-e or <end> | e for end | End of line |
| Ctrl-v or <pgdown> | v looks like a down arrow | Next page |
| Alt-v or <pgup> | Alternative of Ctrl-v | Previous page |
Emacs documentation refers to a Meta key, but on PC keyboards this is the Alt key.
You can also use Meta by hitting Esc and then the key, e.g., Esc then v is the same as Alt-v together.
Search
| Keyboard | Mnemonic | Description |
|---|---|---|
| Ctrl-S | s for search | Search for text |
- Press Ctrl-S
- Start typing the string
- Press Ctrl-S to find more instances
- Press <enter> to stop or press Ctrl-G to cancel
Advanced navigation
Move by words
| Keyboard | Mnemonic | Description |
|---|---|---|
| Alt-f or <right> | f for forward | Forward a character |
| Alt-b or <left> | b for backward | Backward a character |
| Alt-a or <home> | a is beginning of the alphabet | Beginning of sentence |
| Alt-e or <end> | e for end | End of sentence |
Move to top and bottom
| Keyboard | Mnemonic | Description |
|---|---|---|
| Alt-> | > is like a right arrow | End of document |
| Alt-< | < is like a left arrow | Beginning of document |
File handling
| Keyboard | Mnemonic | Description |
|---|---|---|
| Ctrl-x Ctrl-s | s for save | Save file |
| Ctrl-x Ctrl-f | f for file | Open file |
| Ctrl-x Ctrl-w | w for write | Save file under another name |
Can use tab completion when opening files as well
Directory browsing
Emacs also has extensive in-editor file management, such as interactive directory browsers. Try opening a directory instead of a file.
Fun Emacs usage
Buffer management
Window management
File management
Org-mode
Class
Version control and software development
vim
Modes
vim has several modes. Two of them are
- Normal mode: navigating text, saving, quitting, entering commands
- Insert mode: inserting text into the file
This separation of modes makes vim a little unusual compared to other commonly-used, including emacs.
After opening a file, you won't be able to start entering text without entering insert mode.
One benefit of this separation of modes is that vim's common commands are mostly just one or a few keys. No emacs pinky or heavy use of Ctrl and Meta modifiers. All keys are available as commands in normal mode since no text entry is happening in that mode.
Normal mode
- When you open a file, you'll be in normal mode
- Cannot enter text (yet)
- But can navigate and even delete text
Exiting vim
- <Esc> to enter normal mode
- :q to quit
Exit variants
| Key | Description |
|---|---|
| :q | Quit (prompt if unsaved) |
| :wq | Write (save) then quit |
| :q! | Quite without saving (warning: can lose work!) |
Navigation
| Key | Description |
|---|---|
| h | Left |
| j | Down |
| k | Up |
| l | right |
These keys are not unlike the WASD keys in many games. They approximate a physical arrow key layout.
Word-level commands
| Key | Description |
|---|---|
| w | Forward a word |
| e | Forward a word (cursor on end of word) |
| b | Back a word |
Larger movements
| Key | Description |
| 0 | Beginning of line |
| $ | End of line |
| gg | Beginning of file |
| G | End of file |
| ##G | Go to line ## (enter the number first, then type G) |
| /string | Search for a string (type / then the string, then enter) |
| n | Next match (after a search) |
| N | Previous match (after a search) |
Deletion
| Key | Description |
|---|---|
| x | Delete a character (forward) |
| X | Delete a character (backwards) |
| dw | Delete a word (d plus w) |
| de | Delete a word (leaving the space; d plus e) |
| db | Delete a word (d plus b) |
| dd | Delete a line |
| p | Paste last deleted text |
| u | Undo |
Insert mode
| Key | Description |
|---|---|
| i | Start inserting text at cursor point |
| A | Append text at end of line |
Important: use <Esc> to return to normal mode (otherwise normal mode commands will not work and will enter text instead)
Conclusion
- Pick emacs or vim editor
- Or both!
- emacs-like commands used in
bash - vim-like commands used in
less
- emacs-like commands used in
- Use one of these editors in eustis exclusively for class projects