Haskell

Well, my friends, the day has arrived. For thirteen weeks, you have been provided all the conceptual tools to take the leap into the deep end of the functional programming pool and float safely. The great Dr. Erik Meijer has generously given his value time to teach us the fundamentals as delivered…

In Chapter 12, Lazy Evaluation, Dr. Meijer takes us on a journey into the world of order of evaluation (when expressions are evaluated). In the case of lazy evaluation, computation is delayed until the result of the computation is known to be required. Most programming languages that most of…

Yes. You read the title correctly! For today's lecture in the Functional Programming Fundamentals series of lectures the great Dr. Graham Hutton, author of the Programming in Haskell book that Dr. Erik Meijer has based this lecture series on, is guest lecturing Chapter…

In Chapter 10, Declaring Types and Classes, Dr. Meijer teaches us about type declarations, data declarations, arithmetic expressions, etc.  In Haskell, a new name for an existing type can be defined using atype declaration:type String = [Char]String is a synonym for the type [Char].Like…

In Chapter 9, Interactive Programs, Dr. Meijer will teach us how to make programs in Haskell that are side-effecting:interactive. Haskell programs are pure mathematical functions with no side effects. That said, you want to be able to write Haskell programs that can read input from the keyboard and…

In Chapter 8, Functional Parsers, it's all about parsing and parsers. A parser is a program that analyses a piece of text to determine its syntactic structure. In a functional language such as Haskell, parsers can naturallybe viewed as functions.  type Parser = String -> TreeA parser is…

In Chapter 7, Dr. Meijer teaches us about Higher-Order Functions. A function is called higher-order if it takes a function as an argument and returns a function as a result:twice    :: (a -> a) -> a -> atwice f x = f (f x)The function twice above is higher…

In Chapter 6, Dr. Meijer guides us through the world of recursive functions. In Haskell, functions can be defined in terms of themselves.  Such functions are called recursive. For example: factorial 0 = 1factorial (n+1) = (n+1) * factorial nfactorial maps 0 to 1, and…

In Chapter 5, Dr. Meijer introduces and digs into List Comprehensions. In mathematics, comprehension notation is used to construct new sets from old sets. In Haskell, you can create new lists from old lists using a similarcomprehension syntax:[x^2 | x <- [1..5]]The above notation represents the…

In Chapter 3, Dr. Meijer explores types and classes in Haskell. A type is a collection of related values and in Haskell every well-formed expression has a type. Using type inference, these types are automatically calculated at run time. Ifexpression e returns a type t, then e is of type t, e :: t. A…