Haskell and Functional Programming course for complete beginners.

⚠️ The course authors no longer provide reviews of the solutions. However, all the learning materials are free and publicly available. You can learn Haskell on your own or with the help of others.

Course learning materials comprise:

• 🎥 Four 1-hour lectures on YouTube
• 🖼 Slides
• 🧩 Practical exercises and Haskell installation instructions

The course is entirely free!

Below you can find the plan for each individual lecture with the corresponding links to learning materials.

• What is Functional Programming?
• FP concepts
• Haskell features
• Haskell toolchain: GHC, GHCi, ghcup, cabal, hls
• How to install Haskell?
• GHCi
  • Arithmetic expressions
  • Comparison operators
  • Boolean expressions
  • Calling functions
• Types
  • :t command in GHCi
  • Types of booleans, numbers, and functions
• Lists and operations with them
  • Prepending, concatenation
  • Standard list functions
  • Ranges
• Laziness
• String
• Syntax constructions
  • Defining our own functions
  • packages, modules, imports
  • if-then-else
  • guards
  • let-in
  • where
• Immutability
• Recursion
• Higher-Order Functions (HOF)
  • Functions as first-class values
  • Lambda functions
  • Partial application
  • map, filter, etc.

🎞 Slides: https://slides.com/haskellbeginners2022/lecture-1

📽 Video: Haskell Beginners 2022: Lecture 1

• Pattern-matching
  • Top level
  • case-of
  • List patterns
  • Recursion and pattern matching
  • Pattern-matching pitfalls
• Totality
• Tuples
• Algebraic Data Types
  • Product types
  • Sum types
• Data types in Haskell
  • data
  • Simple product types
  • Records
  • Enumerations
  • Simple sum types
  • Recursive data types
  • type
  • newtype
• Polymorphism
  • Parametric polymorphism
  • Types of standard functions
  • Hoogle
  • Polymorphic data types
  • Standard polymorphic data types
• Eta-reduction
• Function composition: dot operator (.)

🎞 Slides: https://slides.com/haskellbeginners2022/lecture-2

📽 Video: Haskell Beginners 2022: Lecture 2

• Parametric polymorphism vs Ad-hoc polymorphism
• Typeclasses
  • class
  • instance
  • Default methods
  • {-# MINIMAL #-}
  • Small typeclasses vs Big typeclasses
• Language Extensions
  • {-# LANGUAGE InstanceSigs #-}
• Standard typeclasses
  • Eq
  • Haskell Equality Table
  • Ord
  • Num
• deriving
  • Stock derivable typeclasses
  • {-# LANGUAGE GeneralizedNewtypeDeriving #-}
• Algebraic typeclasses
  • Semigroup
  • Monoid
  • Laws
• Kinds
• Functor
• Folds
  • foldr
  • foldl
  • foldl'
  • foldr vs foldl'
  • Foldable
• Strict and Lazy evaluation
  • Lazy evaluation
  • Tail Call Optimization (TCO)
  • Equational reasoning
  • {-# LANGUAGE BangPatterns #-}

🎞 Slides: https://slides.com/haskellbeginners2022/lecture-3

📽 Video: Haskell Beginners 2022: Lecture 3

• Monad example
  • andThen for Maybe, Either and list
• Monad as programming pattern
• Monad
  • The typeclass
  • Instances
  • Laws
  • Usage example
• FAMily: Functor, Applicative, Monad
• Purity
• Why Purity + Laziness is a problem for side effects?
• IO
  • Why does IO require a monad?
  • String vs IO String
  • getLine
  • putStrLn
  • Main and main
• Then operator: >>
• do-notation
• Cabal
  • Packages
  • build-depends
• Functional Core, Imperative Shell

🎞 Slides: https://slides.com/haskellbeginners2022/lecture-4

📽 Video: Haskell Beginners 2022: Lecture 4

After you've finished the course, you may be interested in the following resources to continue your FP and Haskell journey:

• Learn Haskell by building a blog generator: A project-based course that teaches pragmatic Haskell by building a blog generator from scratch.
• Haskell in Depth: A book about intermediate Haskell topics such as Monad Transformers, metaprogramming, testing, logging, and performance analysis.
• Functional Design and Architecture : Design patterns and architectures for building production quality applications using functional programming, with examples in Haskell and other FP languages.
• Haskell Study Plan: More links on different topics and examples of real-world Haskell projects.
• Awesome List of Haskell mentors: A list of Haskell projects and mentors willing to help you master Haskell.