> foo
analyze(foo) =  st:foo po:noun xx:other_data
stem(foo) = foo
> foox
analyze(foox) =  st:foo po:noun xx:other_data is:affix_x
stem(foox) = foo
> fooy
analyze(fooy) =  st:foo po:noun xx:other_data ds:affix_y
stem(fooy) = fooy
> fooyx
analyze(fooyx) =  st:foo po:noun xx:other_data ds:affix_y is:affix_x
stem(fooyx) = fooy