key spaces: |
  Normal indent
    One more indent
  Back to normal
folded : >
  Folding is easy to do
    Indenting too
  Roses are blue
foo: bar
another-fold: >-
  fold
  1
  2
  3
yet-another-fold: >+
  another-fold
  11
  12
  13
more-fold: >
  more-fold
  21
  22
  23