- 99 questions
- Learn You a Haskell for Great Good!
- stack manipulation. page 254.
- 257 exersise.
- TypeSynonymInstances, OverlappingInstances
- finally and bracket to make sure close file handles
- Array
- implement binary tree, balanced
- chrome-extension://oemmndcbldboiebfnladdacbdfmadadm/http://dev.stephendiehl.com/hask/tutorial.pdf