• %不表示range的时候，代表当前文件名

Line numbers may be specified with（来自官方文档cmdline.txt）:

    {number}        an absolute line number
    .               the current line                          :.
    $               the last line in the file                 :$
    %               equal to 1,$ (the entire file)            :%
    't              position of mark t (lowercase)            :'
    'T              position of mark T (uppercase); when the mark is in
                    another file it cannot be used in a range
    /{pattern}[/]   the next line where {pattern} matches     :/
    ?{pattern}[?]   the previous line where {pattern} matches :?
    \/              the next line where the previously used search
                    pattern matches
    \?              the previous line where the previously used search
                    pattern matches
    \&              the next line where the previously used substitute
                    pattern matches

参考
:help range