How to set vim as default editor

[Mark <mdevin@ozemail.com.au>]

For some reason after installing and reinstalling vim, ae still remains
the default editor.

when I look in /etc/alternatives I see:
lrwxrwxrwx    1 root     root            7 Apr 30 23:12 editor ->
/bin/ae
lrwxrwxrwx    1 root     root           21 Apr 30 23:12 editor.1.gz ->
/usr/man/man1/ae.1.gz
lrwxrwxrwx    1 root     root           12 Apr 30 23:12 ex ->
/usr/bin/vim
lrwxrwxrwx    1 root     root           28 Apr 30 23:12 ex.1.gz ->
/usr/share/man/man1/vim.1.gz

Is there some debian specific setup script that maintains these links?
I know I can just manually change them to point to vim, but I want to
run the proper program that does it so I know for future reference.

Thanks for help.

Mark.