Modeline Syntax and Limitations in Vim

between ':' is the argument for a ":set" command (can be empty) Examples: vi:noai:sw=3 ts=6 ~ vim: tw=77 ~ The second form (this is compatible with some versions of Vi): [text{white}]{vi:|vim:|Vim:|ex:}[white]se[t] {options}:[text] [text{white}] empty or any text followed by at least one blank character (<Space> or <Tab>); "ex:" always requires at least one blank character {vi:|vim:|Vim:|ex:} the string "vi:", "vim:", "Vim:" or "ex:" [white] optional white space se[t] the string "set " or "se " (note the space); When "Vim" is used it must be "set". {options} a list of options, separated with white space, which is the argument for a ":set" command : a colon [text] any text or empty Examples: > /* vim: set ai tw=75: */ /* Vim: set ai tw=75: */ The white space before {vi:|vim:|Vim:|ex:} is required. This minimizes the chance that a normal word like "lex:" is caught. There is one exception: "vi:" and "vim:" can also be at the start of the line (for compatibility with version 3.0). Using "ex:" at the start of the line will be ignored (this could be short for "example:"). If the modeline is disabled within a modeline, subsequent modelines will be ignored. This is to allow turning off modeline on a per-file basis. This is useful when a line looks like a modeline but isn't. For example, it would be good to start a YAML file containing strings like "vim:" with # vim: nomodeline ~ so as to avoid modeline misdetection. Following options on the same line after modeline deactivation, if any, are still evaluated (but you would normally not have any). *modeline-local* The options are set like with ":setlocal": The new value only applies to the buffer and window that contain the file. Although it's possible to set global options from a modeline, this is unusual. If you have two windows open and the files in it set the same global option to a different value, the result depends on which one was opened last. When editing a file that was already loaded, only the window-local options from the modeline are used. Thus if you manually changed a buffer-local option after opening the file, it won't be changed if you edit the same buffer in another window. But window-local options will be set. *modeline-version* If the modeline is only to be used for some versions of Vim, the version number can be specified where "vim:" or "Vim:" is used: vim{vers}: version {vers} or later vim<{vers}: version before {vers} vim={vers}: version {vers} vim>{vers}: version after {vers} {vers} is 700 for Vim 7.0 (hundred times the major version plus minor). For example, to use a modeline only for Vim 7.0: > /* vim700: set foldmethod=marker */ To use a modeline for Vim after version 7.2: > /* vim>702: set cole=2: */ There can be no blanks between "vim" and the ":". The modeline is ignored if {vers} does not fit in an integer. The number of lines that are checked can be set with the 'modelines' option. If 'modeline' is off or 'modelines' is 0 no lines are checked. Note that for the first form all of the rest of the line is used, thus a line like: > /* vi:ts=4: */ will give an error message for the trailing "*/". This line is OK: > /* vi:set ts=4: */ If an error is detected the rest of the line is skipped. If you want to include a ':' in a set command precede it with a '\'. The backslash in front of the ':' will be removed. Example: > /* vi:set fillchars=stl\:^,vert\:\|: */ This sets the 'fillchars' option to "stl:^,vert:\|". Only a single backslash before the ':' is removed. Thus to include "\:" you have to specify "\\:". *E992* No other commands than "set" are supported, for security reasons (somebody might create a Trojan horse text file with modelines). And not all options can be set. For some options a flag is set, so that when the value is used the |sandbox| is effective. Some options can only be set from the modeline when 'modelineexpr' is set (the default is

This section details the syntax of the two forms of modelines in Vim, used for setting options within a file. It explains the components of each form, including the use of 'vi:', 'vim:', 'Vim:', or 'ex:' prefixes, the 'set' command, and the structure of option settings. It also covers version-specific modelines, the 'modelines' option, and the handling of errors and special characters like ':' within modelines. The section emphasizes the security limitations of modelines, such as the restriction to 'set' commands and the sandboxing of certain options, and introduces 'modelineexpr'.