vim reg for substitution

http://webspace.webring.com/people/do/oleg66/

Meaning
&
the whole matched pattern
\L
the following characters are made lowercase
\0
the whole matched pattern
\U
the following characters are made uppercase
\1
the matched pattern in the first pair of \(\)
\E
end of \U and \L
\2
the matched pattern in the second pair of \(\)
\e
end of \U and \L
...
...
\r
split line in two at this point
\9
the matched pattern in the ninth pair of \(\)
\l
next character made lowercase
~
the previous substitute string
\u
next character made uppercase