[20191130]vim modeline.txt

--//今天编辑文件,发现每次打开老是报错,提示类似如下:
处理 modelines 时发生错误:
第    3 行:
E518: 未知的选项: this

$ cat a.txt

for ex: this is a test

--//输入:help modeline,看到如下:

There are two forms of modelines.  The first form:
    [text]{white}{vi:|vim:|ex:}[white]{options}

[text]        any text or empty
{white}        at least one blank character ( or )
{vi:|vim:|ex:}    the string "vi:", "vim:" or "ex:"
[white]        optional white space
{options}    a list of option settings, separated with white space or ':',
        where each part between ':' is the argument for a ":set"
        command (can be empty)

Example:
   vi:noai:sw=3 ts=6 ~

The second form (this is compatible with some versions of Vi):

    [text]{white}{vi:|vim:|ex:}[white]se[t] {options}:[text]

[text]        any text or empty
{white}        at least one blank character ( or )
{vi:|vim:|ex:}    the string "vi:", "vim:" or "ex:"
[white]        optional white space
se[t]        the string "set " or "se " (note the space)
{options}    a list of options, separated with white space, which is the
        argument for a ":set" command
:        a colon
[text]        any text or empty

Example:
   /* vim: set ai tw=75: */

The white space before {vi:|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:").

--//原来这种模式控制文件的显示模式以及设置,做一个记录.一般在开头以及结尾的5行.
--//一些开发会使用一些特殊的定义.
--//假设定义如下,打开文件就会在列10,20,40出现彩色的竖线
/* vim: set colorcolumn=10,20,40: */