WIP: Vim highlight private section of Ruby

wip_private_ruby.vim

function! Snake()
ruby << EOF
  b = Vim::Buffer.current
  line_count = b.length
  indexed_lines = line_count.times.map { |i| [ i, b[i + 1] ] }

  matches = indexed_lines.select { |i, line| line.match(/^\s+private$/) }

  matches.each { |priv_i, priv_text|
    re = /^#{priv_text.sub("  private", "end")}$/
    end_i, _ = indexed_lines[priv_i..-1].find { |i, line| line.match(re) }

    from_line = priv_i + 1
    to_line = end_i + 1

    p [ from_line, to_line ]

    Vim::command %{call matchadd('Error', '\\%>#{from_line}l\\%<#{to_line}l.*')}
  }
EOF
endfunction

command! Snake :call Snake()