Execute selected ruby into inline comments

inline_ruby.vim

" Inline ruby interpretation, inspired by RubyTapas.
"
" Example output when run over the top line:
"
"     3.times { |num| puts num }
"     # => 0
"     # => 1
"     # => 2
"
vmap <leader>r :!tee >(cat) \| ruby \| sed 's/^/\\# \=> /'<cr>

Broken down:

• tee pipes to two commands, the first is cat that just repeats what it gets to not replace the original code
• ruby outputs the result when things are piped to it
• sed puts the comments in front of the result, with some wonky escaping

This is basically a poor man's seeing is believing in one line. Obviously much worse but still cool.