Vi_diff

Differences between Vim and Vi

Vim has only a few limits for the files that can be edited. Vi cannot handle <Nul> characters and characters above 128, has limited line length, many other limits.

Maximum line length 2147483647 characters Maximum number of lines 2147483647 lines Maximum file size 2147483647 bytes (2 Gbyte) when a long integer is 32 bits. Much more for 64 bit longs. Also limited by available disk space for the swap-file. E75 Length of a file path Unix and Win32: 1024 characters, otherwise 256 characters (or as much as the system supports). Length of an expanded string option Unix and Win32: 1024 characters, otherwise 256 characters Maximum display width Unix and Win32: 1024 characters, otherwise 255 characters Maximum lhs of a mapping 50 characters. Number of different highlighting types: over 30000 Range of a Number variable: -2147483648 to 2147483647 (might be more on 64 bit systems) Maximum length of a line in a tags file: 512 bytes.

Information for undo and text in registers is kept in memory, thus when making (big) changes the amount of (virtual) memory available limits the number of undo levels and the text that can be kept in registers. Other things are also kept in memory: Command-line history, error messages for Quickfix mode, etc.

Support for different systems. Vim can be used on:

Multi level persistent undo. undo 'u' goes backward in time, 'CTRL-R' goes forward again. Set option 'undolevels' to the number of changes to be remembered (default 1000). Set 'undolevels' to 0 for a Vi-compatible one level undo. Set it to -1 for no undo at all. When all changes in a buffer have been undone, the buffer is not considered changed anymore. You can exit it with :q, without <!>. When undoing a few changes and then making a new change Vim will create a branch in the undo tree. This means you can go back to any state of the text, there is no risk of a change causing text to be lost forever. undo-tree The undo information is stored in a file when the 'undofile' option is set. This means you can exit Vim, start Vim on a previously edited file and undo changes that were made before exiting Vim.

Graphical User Interface (GUI). gui Included support for GUI: menu's, mouse, scrollbars, etc. You can define your own menus. Better support for CTRL/SHIFT/ALT keys in combination with special keys and mouse. Supported for various platforms such as Win32.

Multiple windows and buffers. windows.txt Vim can split the screen into several windows, each editing a different buffer or the same buffer at a different location. Buffers can still be loaded (and changed) but not displayed in a window. This is called a hidden buffer. Many commands and options have been added for this facility. Vim can also use multiple tab pages, each with one or more windows. A line with tab labels can be used to quickly switch between these pages. tab-page

Syntax highlighting. :syntax Vim can highlight keywords, patterns and other things. This is defined by a number of :syntax commands, and can be made to highlight most languages and file types. A number of files are included for highlighting the most common languages, like C, C++, Java, Pascal, Makefiles, shell scripts, etc. The colors used for highlighting can be defined for ordinary terminals, color terminals and the GUI with the :highlight command. A convenient way to do this is using a :colorscheme command. The highlighted text can be exported as HTML. convert-to-HTML Other items that can be highlighted are matches with the search string 'hlsearch', matching parens matchparen and the cursor line and column 'cursorline' 'cursorcolumn'.

Spell checking. spell When the 'spell' option is set Vim will highlight spelling mistakes. About 50 languages are currently supported, selected with the 'spelllang' option. In source code only comments and strings are checked for spelling.

Folding. folding A range of lines can be shown as one "folded" line. This allows overviewing a file and moving blocks of text around quickly. Folds can be created manually, from the syntax of the file, by indent, etc.

Diff mode. diff-mode Vim can show two versions of a file with the differences highlighted. Parts of the text that are equal are folded away. Commands can be used to move text from one version to the other.

Plugins. add-plugin The functionality can be extended by dropping a plugin file in the right directory. That's an easy way to start using Vim scripts written by others. Plugins can be for all kind of files, or specifically for a filetype. Packages make this even easier. packages

Asynchronous communication and timers. job-control timer Vim can exchange messages with other processes in the background. Vim can start a job, communicate with it and stop it. job-control Timers can fire once or repeatedly and invoke a function to do any work. timer

Repeat a series of commands. q "q{c}" starts recording typed characters into named register {c}. A subsequent "q" stops recording. The register can then be executed with the "@{c}" command. This is very useful to repeat a complex action.

Flexible insert mode. ins-special-special The arrow keys can be used in insert mode to move around in the file. This breaks the insert in two parts as far as undo and redo is concerned.

CTRL-O can be used to execute a single Normal mode command. This is almost the same as hitting <Esc>, typing the command and doing a.

Visual mode. Visual-mode Visual mode can be used to first highlight a piece of text and then give a command to do something with it. This is an (easy to use) alternative to first giving the operator and then moving to the end of the text to be operated upon. v and V are used to start Visual mode. v works on characters and V on lines. Move the cursor to extend the Visual area. It is shown highlighted on the screen. By typing "o" the other end of the Visual area can be moved. The Visual area can be affected by an operator: d delete c change y yank > or < insert or delete indent ! filter through external program = filter through indent : start : command for the Visual lines. gq format text to 'textwidth' columns J join lines ~ swap case u make lowercase U make uppercase

Block operators. visual-block With Visual mode a rectangular block of text can be selected. Start Visual mode with CTRL-V. The block can be deleted ("d"), yanked ("y") or its case can be changed ("~", "u" and "U"). A deleted or yanked block can be put into the text with the "p" and "P" commands.

Help system. :help Help is displayed in a window. The usual commands can be used to move around, search for a string, etc. Tags can be used to jump around in the help files, just like hypertext links. The :help command takes an argument to quickly jump to the info on a subject. <F1> is the quick access to the help system. The name of the help index file can be set with the 'helpfile' option.

Command-line editing and history. cmdline-editing You can insert or delete at any place in the command-line using the cursor keys. The right/left cursor keys can be used to move forward/backward one character. The shifted right/left cursor keys can be used to move forward/backward one word. CTRL-B/CTRL-E can be used to go to the begin/end of the command-line. (Vi: can only alter the last character in the line) (Vi: when hitting <Esc> the command-line is executed. This is unexpected for most people; therefore it was changed in Vim. But when the <Esc> is part of a mapping, the command-line is executed. If you want the Vi behaviour also when typing <Esc>, use ":cmap ^V<Esc> ^V^M") cmdline-history The command-lines are remembered. The up/down cursor keys can be used to recall previous command-lines. The 'history' option can be set to the number of lines that will be remembered. There is a separate history for commands and for search patterns.

Command-line completion. cmdline-completion While entering a command-line (on the bottom line of the screen) <Tab> can be typed to complete

If there are multiple matches, CTRL-N (next) and CTRL-P (previous) will walk through the matches. <Tab> works like CTRL-N, but wraps around to the first match.

The 'wildchar' option can be set to the character for command-line completion, <Tab> is the default. CTRL-D can be typed after an (incomplete) wildcard; all matches will be listed. CTRL-A will insert all matches. CTRL-L will insert the longest common part of the matches.

Insert-mode completion. ins-completion In Insert mode the CTRL-N and CTRL-P keys can be used to complete a word that appears elsewhere. i_CTRL-N With CTRL-X another mode is entered, through which completion can be done for: i_CTRL-X_CTRL-F file names i_CTRL-X_CTRL-K words from 'dictionary' files i_CTRL-X_CTRL-T words from 'thesaurus' files i_CTRL-X_CTRL-I words from included files i_CTRL-X_CTRL-L whole lines i_CTRL-X_CTRL-] words from the tags file i_CTRL-X_CTRL-D definitions or macros i_CTRL-X_CTRL-O Omni completion: clever completion specifically for a file type etc.

Long line support. 'wrap' 'linebreak' If the 'wrap' option is off, long lines will not wrap and only part of them will be shown. When the cursor is moved to a part that is not shown, the screen will scroll horizontally. The minimum number of columns to scroll can be set with the 'sidescroll' option. The zh and zl commands can be used to scroll sideways. Alternatively, long lines are broken in between words when the 'linebreak' option is set. This allows editing a single-line paragraph conveniently (e.g. when the text is later read into a DTP program). Move the cursor up/down with the gk and gj commands.

Text formatting. formatting The 'textwidth' option can be used to automatically limit the line length. This supplements the 'wrapmargin' option of Vi, which was not very useful. The gq operator can be used to format a piece of text (for example, gqap formats the current paragraph). Commands for text alignment: :center, :left and :right.

Extended search patterns. pattern There are many extra items to match various text items. Examples: A "\n" can be used in a search pattern to match a line break. "x\{2,4}" matches "x" 2 to 4 times. "\s" matches a white space character.

Directory, remote and archive browsing. netrw Vim can browse the file system. Simply edit a directory. Move around in the list with the usual commands and press <Enter> to go to the directory or file under the cursor. This also works for remote files over ftp, http, ssh, etc. Zip and tar archives can also be browsed. tar zip

Edit-compile-edit speedup. quickfix The :make command can be used to run the compilation and jump to the first error. A file with compiler error messages is interpreted. Vim jumps to the first error.

Each line in the error file is scanned for the name of a file, line number and error message. The 'errorformat' option can be set to a list of scanf-like strings to handle output from many compilers.

The :cn command can be used to jump to the next error. :cl lists all the error messages. Other commands are available. The 'makeef' option has the name of the file with error messages. The 'makeprg' option contains the name of the program to be executed with the :make command. The 'shellpipe' option contains the string to be used to put the output of the compiler into the errorfile.

Finding matches in files. :vimgrep Vim can search for a pattern in multiple files. This uses the advanced Vim regexp pattern, works on all systems and also works to search in compressed files.

Improved indenting for programs. 'cindent' When the 'cindent' option is on the indent of each line is automatically adjusted. C syntax is mostly recognized. The indent for various styles can be set with 'cinoptions'. The keys to trigger indenting can be set with 'cinkeys'.

Comments can be automatically formatted. The 'comments' option can be set to the characters that start and end a comment. This works best for C code, but also works for e-mail (">" at start of the line) and other types of text. The = operator can be used to re-indent lines.

For many other languages an indent plugin is present to support automatic indenting. 30.3

Searching for words in included files. include-search The [i command can be used to search for a match of the word under the cursor in the current and included files. The 'include' option can be set to a pattern that describes a command to include a file (the default is for C programs). The [I command lists all matches, the [_CTRL-I command jumps to a match. The [d, [D and [_CTRL-D commands do the same, but only for lines where the pattern given with the 'define' option matches.

Automatic commands. autocommand Commands can be automatically executed when reading a file, writing a file, jumping to another buffer, etc., depending on the file name. This is useful to set options and mappings for C programs, documentation, plain text, e-mail, etc. This also makes it possible to edit compressed files.

Scripts and Expressions. expression Commands have been added to form up a powerful script language. :if Conditional execution, which can be used for example to set options depending on the value of $TERM. :while Repeat a number of commands. :for Loop over a list. :echo Print the result of an expression. :let Assign a value to an internal variable, option, etc. Variable types are Number, String, List and Dictionary. :execute Execute a command formed by an expression. :try Catch exceptions. etc., etc. See eval. Debugging and profiling are supported. debug-scripts profile If this is not enough, an interface is provided to Python.

Viminfo. The command-line history, marks and registers can be stored in a file that is read on startup. This can be used to repeat a search command or command-line command after exiting and restarting Vim. It is also possible to jump right back to where the last edit stopped with '0. The 'viminfo' option can be set to select which items to store in the .viminfo file. This is off by default.

Mouse support. mouse-using The mouse is supported in the GUI version, in an xterm for Unix, for BSDs with sysmouse, for Linux with gpm, and for Win32. It can be used to position the cursor, select the visual area, paste a register, etc.

Usage of key names. <> key-notation Special keys now all have a name like <Up>, <End>, etc. This name can be used in mappings, to make it easy to edit them.

Editing binary files. edit-binary Vim can edit binary files. You can change a few characters in an executable file, without corrupting it. Vim doesn't remove NUL characters (they are represented as <NL> internally). -b command-line argument to start editing a binary file 'binary' Option set by -b. Prevents adding an <EOL> for the last line in the file.

Multi-language support. multi-lang Files in double-byte or multibyte encodings can be edited. There is UTF-8 support to be able to edit various languages at the same time, without switching fonts. UTF-8 Messages and menus are available in different languages.

Move cursor beyond lines. When the 'virtualedit' option is set the cursor can move all over the screen, also where there is no text. This is useful to edit tables and figures easily.