Editing Deterministic algorithm (section)

== Determinism categories in languages ==

=== Mercury ===
The [[Mercury (programming language)|mercury]] logic-functional programming language establishes different determinism categories for predicate modes as explained in the reference.<ref>{{Cite web |url=http://www.mercury.csse.unimelb.edu.au/information/doc-release/mercury_ref/Determinism-categories.html |title=Determinism categories in the Mercury programming language |access-date=2013-02-23 |archive-url=https://web.archive.org/web/20120703001434/http://www.mercury.csse.unimelb.edu.au/information/doc-release/mercury_ref/Determinism-categories.html#Determinism-categories |archive-date=2012-07-03 |url-status=dead }}</ref><ref>{{Cite web |url=http://www.mercury.csse.unimelb.edu.au/information/doc-release/mercury_ref/Predicate-and-function-mode-declarations.html |title=Mercury predicate modes |access-date=2013-02-25 |archive-url=https://web.archive.org/web/20120703001411/http://www.mercury.csse.unimelb.edu.au/information/doc-release/mercury_ref/Predicate-and-function-mode-declarations.html#Predicate-and-function-mode-declarations |archive-date=2012-07-03 |url-status=dead }}</ref>

=== Haskell ===
[[Haskell]] provides several mechanisms:
* Non-determinism or notion of Fail
** the ''Maybe'' and ''Either'' types include the notion of success in the result.
** the ''fail'' method of the class Monad, may be used to signal ''fail'' as exception.
** the Maybe [[Monad (functional programming)|monad]] and MaybeT monad transformer provide for failed computations (stop the computation sequence and return Nothing)<ref>{{cite web|url=http://www.haskell.org/haskellwiki/Monad#Common_monads |title=Representing failure using the Maybe monad}}</ref>
* Neterminism/non-det with multiple solutions
** you may retrieve all possible outcomes of a multiple result computation, by wrapping its result type in a MonadPlus [[Monad (functional programming)|monad]]. (its method ''mzero'' makes an outcome fail and ''mplus'' collects the successful results).<ref name="monad-plus">{{cite web|url=http://www.haskell.org/haskellwiki/MonadPlus |title=The class MonadPlus}}</ref>

=== ML family and derived languages ===

As seen in [[Standard ML]], [[OCaml]] and [[Scala (programming language)|Scala]]
* The ''option'' type includes the notion of success.

=== Java ===
In [[Java (programming language)|Java]], the ''null'' reference value may represent an unsuccessful (out-of-domain) result.