Operator definition
added Token datatype declaration
start of excersises
completed 5. chapter
added string function
finished chapter 6
map and filter excersise
chapter 7 work
start learning from http://learnyouahaskell.com/types-and-typeclasses
Started http://learnyouahaskell.com/syntax-in-functions
Finished http://learnyouahaskell.com/recursion
Working http://learnyouahaskell.com/higher-order-functions
Finished http://learnyouahaskell.com/higher-order-functions
Start of http://learnyouahaskell.com/making-our-own-types-and-typeclasses
In the middle of http://learnyouahaskell.com/making-our-own-types-and-typeclasses