+<p>
+* [[!wikipedia Tagged union]]
+* [[!wikipedia Algebraic data type]]
+* [[!wikipedia Recursive data type]]
+* [[!wikipedia Pattern matching]]
+* [[!wikipedia Unit type]]
+* [[!wikipedia Bottom type]]
+
+
+##[[Learning OCaml]]##
+
+
+## Monads ##
+* [[!wikipedia Monad (functional programming) desc="Monads in Functional Programming"]]
+* [Daniel Friedman. A Schemer's View of Monads](/schemersviewofmonads.ps): from <https://www.cs.indiana.edu/cgi-pub/c311/doku.php?id=home> but the link above is to a local copy.
+* [A Gentle Intro to Haskell: About Monads](http://www.haskell.org/tutorial/monads.html)
+* [All About Monads](http://haskell.org/all_about_monads/html/index.html)
+* From HaskwellWiki:
+ [Monad tutorials timeline](http://www.haskell.org/haskellwiki/Monad_tutorials_timeline)
+ [Monad laws](http://www.haskell.org/haskellwiki/Monad_Laws)
+ [Monads as computation](http://www.haskell.org/haskellwiki/Monads_as_computation)
+ [Monads as containers](http://www.haskell.org/haskellwiki/Monads_as_containers)
+ [What a monad is not](http://www.haskell.org/haskellwiki/What_a_Monad_is_not)
+* [Haskell wikibook: Understanding monads](http://en.wikibooks.org/wiki/Haskell/Understanding_monads)
+
+* [You Could Have Invented Monads! (And Maybe You Already Have.)](http://blog.sigfpe.com/2006/08/you-could-have-invented-monads-and.html)
+* Yet Another Monad Tutorial: [part 1](http://mvanier.livejournal.com/3917.html) [part 2](http://mvanier.livejournal.com/4305.html)
+* [Monads for the Working Haskell Programmer -- a short tutorial](http://www.engr.mun.ca/~theo/Misc/haskell_and_monads.htm)
+* [Introduction to Haskell: Monads](http://onlamp.com/pub/a/onlamp/2007/08/02/introduction-to-haskell-pure-functions.html)
+* [SPb Haskell User Group: Monad tutorial](http://spbhug.folding-maps.org/wiki/MonadsEn)
+* [Understanding Haskell Monads](http://ertes.de/articles/monads.html)
+* [A Monad Tutorial for OCaml](http://enfranchisedmind.com/blog/posts/a-monad-tutorial-for-ocaml/)
+* [Beyond Monads](http://blog.sigfpe.com/2009/02/beyond-monads.html)
+* [Simple Explanation of a Monad](http://math.stackexchange.com/questions/405/simple-explanation-of-a-monad)
+* [What is a Monad?](http://stackoverflow.com/questions/44965/what-is-a-monad)
+* [Can Anyone Explain Monads?](http://stackoverflow.com/questions/2366/can-anyone-explain-monads)
+* [Monad in Plain English...](http://stackoverflow.com/questions/2704652/monad-in-plain-english-for-the-oop-programmer-with-no-fp-background)
+* [Monad in non-programming terms](http://stackoverflow.com/questions/3261729/monad-in-non-programming-terms)
+* [Real World Haskell: chapter on Monads](http://book.realworldhaskell.org/read/monads.html)
+* [Learn You a Haskell for Great Good: chapter on Functors, Applicative Functors and Monoids](http://www.learnyouahaskell.com/functors-applicative-functors-and-monoids)
+* Monads are Elephants:
+[Part 1](http://james-iry.blogspot.com/2007/09/monads-are-elephants-part-1.html)
+[Part 2](http://james-iry.blogspot.com/2007/10/monads-are-elephants-part-2.html)
+[Part 3](http://james-iry.blogspot.com/2007/10/monads-are-elephants-part-3.html)
+[Part 4](http://james-iry.blogspot.com/2007/11/monads-are-elephants-part-4.html)
+* [Brian Beckman: Don't fear the Monad (67 minute video)](http://channel9.msdn.com/shows/Going+Deep/Brian-Beckman-Dont-fear-the-Monads/)
+* [A monad non-tutorial...or why you shouldn't ask what a monad is](http://strongtyped.blogspot.com/2010/01/monad-non-tutorial.html)
+* [Abstraction, intuition, and the "monad tutorial fallacy"](http://byorgey.wordpress.com/2009/01/12/abstraction-intuition-and-the-monad-tutorial-fallacy/)
+* [How you should(n't) use Monad](http://noordering.wordpress.com/2009/03/31/how-you-shouldnt-use-monad/)
+* [The Mother of all Monads](http://blog.sigfpe.com/2008/12/mother-of-all-monads.html)
+* [Monads! (and Why Monad Tutorials Are All Awful)](http://ahamsandwich.wordpress.com/2007/07/26/monads-and-why-monad-tutorials-are-all-awful/)
+* [Of monads and spacesuits (archived)](http://www.iterasi.net/openviewer.aspx?sqrlitid=ixx7fcluvek_9lfolsxr_g)
+* [How not to explain Haskell monads](http://mvanier.livejournal.com/1205.html)
+* [The State Monad: a tutorial for the confused?](http://coder.bsimmons.name/blog/2009/10/the-state-monad-a-tutorial-for-the-confused/)
+* Haskell state monads: [part 1](http://mvanier.livejournal.com/1765.html) [part 2](http://mvanier.livejournal.com/1901.html)
+ [part 3](http://mvanier.livejournal.com/4586.html) [part 4](http://mvanier.livejournal.com/4647.html)
+
+<p>
+* [Research Papers/Monads and Arrows](http://www.haskell.org/haskellwiki/Research_papers/Monads_and_arrows)
+* [Eugenio Moggi, Notions of Computation and Monads](http://www.disi.unige.it/person/MoggiE/ftp/ic91.pdf): Information and Computation 93 (1) 1991.
+* [Philip Wadler. Monads for Functional Programming](http://homepages.inf.ed.ac.uk/wadler/papers/marktoberdorf/baastad.pdf):
+in M. Broy, editor, *Marktoberdorf Summer School on Program Design Calculi*, Springer Verlag, NATO ASI Series F: Computer and systems sciences, Volume 118, August 1992. Also in J. Jeuring and E. Meijer, editors, *Advanced Functional Programming*, Springer Verlag, LNCS 925, 1995. Some errata fixed August 2001.
+<!-- The use of monads to structure functional programs is described. Monads provide a convenient framework for simulating effects found in other languages, such as global state, exception handling, output, or non-determinism. Three case studies are looked at in detail: how monads ease the modification of a simple evaluator; how monads act as the basis of a datatype of arrays subject to in-place update; and how monads can be used to build parsers.-->
+* [Philip Wadler. The essence of functional programming](http://homepages.inf.ed.ac.uk/wadler/papers/essence/essence.ps):
+invited talk, *19'th Symposium on Principles of Programming Languages*, ACM Press, Albuquerque, January 1992.
+<!-- This paper explores the use monads to structure functional programs. No prior knowledge of monads or category theory is required.
+ Monads increase the ease with which programs may be modified. They can mimic the effect of impure features such as exceptions, state, and continuations; and also provide effects not easily achieved with such features. The types of a program reflect which effects occur.
+ The first section is an extended example of the use of monads. A simple interpreter is modified to support various extra features: error messages, state, output, and non-deterministic choice. The second section describes the relation between monads and continuation-passing style. The third section sketches how monads are used in a compiler for Haskell that is written in Haskell.-->
+
+<p>
+* Ken Shan [Monads for natural language semantics](http://arxiv.org/abs/cs/0205026v1) (2001) uses reader monad to implement intensionality.
+* Ben-Avi and Winter [A modular approach to intensionality](http://parles.upf.es/glif/pub/sub11/individual/bena_wint.pdf) (2007) reinvents the technique.
+ <!--http://citeseerx.ist.psu.edu/viewdocsummary?doi=10.1.1.73.6927-->
+* Monsters and context-shifting, e.g. Gillies/von Fintel on "ifs" [not sure which paper]
+
+
+## Monads in Category Theory ##
+
+* [Category Theory at SEP](http://plato.stanford.edu/entries/category-theory/)
+* [[!wikipedia Category theory]]
+* [[!wikipedia Category (mathematics) desc="Category"]]
+* [[!wikipedia Morphism]]
+* [[!wikipedia Functor]]
+* [[!wikipedia Natural transformation]]
+* [[!wikipedia Monad (category theory) desc="Monads in category theory"]]
+* [Haskell/Category Theory](http://en.wikibooks.org/wiki/Haskell/Category_theory)
+* [Category Theory & Functional Programming](http://blog.mestan.fr/2009/01/09/category-theory-functional-programming/)
+* [Learning Haskell through Category Theory, and Adventuring in Category Land](http://dekudekuplex.wordpress.com/2009/01/16/learning-haskell-through-category-theory-and-adventuring-in-category-land-like-flatterland-only-about-categories/)
+* [Resources for learning practical category theory](http://mathoverflow.net/questions/903/resources-for-learning-practical-category-theory)
+* [A Partial Ordering of some Category Theory applied to Haskell](http://blog.sigfpe.com/2010/03/partial-ordering-of-some-category.html)
+