Mercury is a Programming Language descended from the Prolog Language.

From the project site (http://www.mercury.csse.unimelb.edu.au/) ''with some WikiWord''''''s sneaked in'':

What is Mercury?

LogicProgramming languages have been around since about 1970 (Prolog and Micro''''''Planner). Despite the expected advantages of a very HighLevelLanguage based upon well developed theories of logic over conventional programming languages (such as CeeLanguage, CeePlusPlus, PascalLanguage and AdaLanguage) they have not had significant impact on the computer industry. 

Mercury is a new logic/FunctionalProgrammingLanguage which combines the clarity and expressiveness of DeclarativeProgramming with advanced static analysis and error detection features. Its highly optimized execution algorithm delivers efficiency far in excess of existing logic programming systems, and close to conventional programming systems. Mercury addresses the problems of large-scale program development, allowing modularity, separate compilation, and numerous optimization/time trade-offs. 

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See http://www.mercury.csse.unimelb.edu.au/information/comparison_with_haskell.html for a comparison of Mercury with the HaskellLanguage.

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CategoryProgrammingLanguage