If you want to map multiple commands in vim do it like this:
This writes the actual file to disk and evaluates it through the ruby interpreter when you hit the F1-key.
Alternatively you can do a:
:nmap <F1> :w|rubyf %<CR> (no space after the %)
:imap <F1> <Esc>:w|rubyf %<CR>
which should be faster, condition is you have to build vim with ruby support, but sometimes i get no results with this , vim gets crashed or does not respond anymore to me...
This mappings work both in insert- and command-mode