howto correct 7etc to /etc ?

[Andy Spiegl <zsh.Andy@xxxxxxxxx>]

I'd like to configure my completion so that when I type
 $ ls 7etc<TAB>

it corrects the mistyped 7 to   (note: on German keyboards / is shift-7)
 $ ls /etc
but only if the 7 is the first character of a path and if there isn't any
real file or directory that starts with a 7.  Unfortunately "_correct"
doesn't do the job in this case.

Can that be done?  My first guess was to take _expand_dots and modify it
but I must admit that I am still not enough of a zsh-guru to be able to do
it by myself.

Thanks for any hint,
 Andy.

-- 
                              o      _     _         _
  ------- __o       __o      /\_   _ \\o  (_)\__/o  (_)          -o)
  ----- _`\<,_    _`\<,_    _>(_) (_)/<_    \_| \   _|/' \/       /\\
  ---- (_)/ (_)  (_)/ (_)  (_)        (_)   (_)    (_)'  _\o_    _\_v
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 Acupuncture is a jab well done.