gistfile1.txt

if is_yak then
    shave yak
    bathe yak
  else
    do productive_work

--> (if is_yak then
        ((shave yak)
         (bathe yak))
     else
        ((do productive_work))
    )

for yak in yaks first
    print "Here are some yaks:"
  then
    print yak
  last
    print "And that's all the yaks!"
  empty
    print "I'm afraid there are no yaks."


if is_yak then
    shave yak
  elif is_gerbil then
    preen gerbil
  else
    cheer


# One possible way to parse this:
sentences    = sentence+  # starting point
sentence     = line blocks?
line         = word+ newline
blocks       = indent sentences other_blocks? outdent
other_blocks = partial_outdent other_block+
other_block  = line indent sentences outdent