% [Phooey](http://haskell.org/haskellwiki/Phooey) To Do
+ Even out the stretching between sub-layouts. I nest binary layout
operators, and I think the stretch space is divided in two each time.
Look for *associative* layout operators. I may have to make my own
layout data type that holds lists of layouts, so I can append them.
Right now, I just make rows, columns, boxed, and widget (with fill), so
the data type could reflect those tools.
+ Consider rewriting `Phooey.Monad` to use mtl-style operations instead of
working on `UI'`.