Monad tutorials timeline

before 2000

• 1992-08 Monads for Functional Programming - Phil Wadler

  "Shall I be pure or impure?" One of the earliest papers on monads by the man hiself. Has been called the "ne plus ultra of approachable, useful introductions to monads". It's pretty hefty (31 pages), which is a good thing!

• ???? Monads for the working Haskell Programmer - Theodore S. Norvell

  One of the original tutorials, eventually "updated for Haskell98"

2002

• 2002 Yet Another Haskell Tutorial - Hal Daumé III

  The most recommended Haskell tutorial ever. Not a monad tutorial per se, but it does address the topic

2003

• 2003-08 All about Monads - Jeff Newbern

  A comprehensive introduction to monads, covering also "advanced" topics like monad transformers and use of some common monads. There is an appendix which presents monads as assembly lines.

2004

• 2004-07 Monads as Containers - Cale Gibbard

  Presents monads as boxes. Uses fmap and join. "If you will give me a blueberry for each apple I give you (a -> b), and I have a box of apples (f a), then I can get a box of blueberries (f b)."

• 2004-08 Monads in Perl - Greg Buchholz

  Written in the spirit of TMTOWTDI

2005

• 2005-07 Monads in Ruby - MenTaLguY

  Who said monads were special to Haskell?

• 2005-11 Of monads and space suits - Eric Kow

  Functions are space stations, parameters are astronauts and monads are space suits that let us safely travel from one function to another.

2006

• 2006-03 Understanding Monads - Eric Kow

  Monads as nuclear waste containers, an adaptation of monads as space suits with a new metaphor suggested by Paul Johnson

• 2006-07 The Monadic Way - Andrea Rossato

  A two-part tutorial. The first part shows you how build a simple evaluator, and the second part shows you how to "take the complexity" out of it by using techniques such as monad transformers

• 2006-08 You could have invented monads! (and maybe you already have) - Dan Piponi

  "Writing introductions to monads seems to have developed into an industry," Dan (sigfpe) observes. He argues that monads are not "something esoteric in need of explanation", but walks you through the process of reinventing monads to solve some very basic and practical problems.

• 2006-09 Meet Bob The Monadic Lover - Andrea Rossato

  Bob embarks upon a series of romantic conquests... bind bind bind, Paula, Luisa, Antonia

• 2006-10 Monad Transformers Step by Step - Martin Grabmüller
  • Monad transformers are rarely covered in introductory tutorials. This "is not a paper about implementing transformers, but about using them to write elegant, clean and powerful programs in Haskell". Available as a 12 page PDF or .lhs file.
• 2006-11 There's a Monster in my Haskell! Andrew Pimlott

  This delightful "tutorial" presents monads as monsters which devour values, use them to feed other monsters and regurgitate them when slain.

• 2006-12 Maybe Monad in Java - Tony Morris

  Monads can also be useful in Java!

2007

• 2007-01 Think of a monad - Don Stewart (reposted on Eric Kow's blog)

  Don integrates some pre-existing monadic metaphors, shedding light on monads in a truly comprehensive manner (illustration by Eric)

• 2007-02 Understanding Monads. For Real - Karsten Wagner

  A monad is like a macro

• 2007-04 The Real Monad Transformer - Henning Thielemann

  Not a tutorial either, but an important aid in demystifying monads

• 2007-03 Monads in 15 Minutes - Eric Kidd

  Eric boils monads down to 15 minutes, using backtracking and Maybe as motivating examples. Eric uses join, which seems quite rare for monad tutorials (cf Cale's Monads as containers)

• 2007-07 Monads! (and why monad tutorials are all awful) - Colin Gordon?

  Csgordon reports that monad tutorials tend to "get horribly botched" and "either bored [him] to tears, struck [him] as completely inane, or simply confused [him]". He uncovers Phil Wadler's original 1995 paper, which not only gives a clear explanation but provides non-trivial motivating examples

• 2007-08 Monads as computation - Cale Gibbard

  A very straightforward presentation of monads. Notable for its "The whole point" section, which conveys way we bother if all this monad business.

• 2007-08 Understanding Monads (2) - Apfelmus

  Wikibook rewrite of the original monads tutorial. Less fluff, more pedagogy. [In progress at the time of this writing].

• 2007-08 Monad (sans metaphors) - Claus Reinke

  From a discussion about monad tutorials on Haskell Café (the name is due to haskellwiki user 'Green tea').