vim regex中'\％'和'\ @'令牌的名称是什么？它是做什么的？

在编辑语法文件时，我发现类似以下内容：

\s*\%(\%(:\@<!\/\/.*\)\=\|\%(\/\*.*\*\/\s*\)*\)$

除了那里以外\%，我都不熟悉\@。我什至无法搜索，因为我不知道它的名字。那么它是什么，它做什么呢？

谷歌搜索前，请尝试以下文档：

从 :h \%

\%(\)   A pattern enclosed by escaped parentheses.
    Just like \(\), but without counting it as a sub-expression.  This
    allows using more groups and it's a little bit faster.
    {not in Vi}

和 :h \@<!

\@<!    Matches with zero width if the preceding atom does NOT match just
    before what follows.  Thus this matches if there is no position in the
    current or previous line where the atom matches such that it ends just
    before what follows.

    Like "(?<!pattern)" in Perl, but Vim allows non-fixed-width patterns.
    The match with the preceding atom is made to end just before the match
    with what follows, thus an atom that ends in ".*" will work.
    Warning: This can be slow (because many positions need to be checked
    for a match).  Use a limit if you can, see below.

    Example         matches ~

    \(foo\)\@<!bar      any "bar" that's not in "foobar"

    \(\/\/.*\)\@<!in    "in" which is not after "//"