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This is the reference distribution of Gemooy, an esoteric programming language designed by Chris Pressey on December 2, 2010.
It contains a document describing Gemooy which shall be considered, in lieu of anything more rigorous, the specification of the language: doc/Gemooy.md.
It contains an implementation of Gemooy in Javascript which shall be considered, in lieu of anything more formal, the reference implementation: src/gemooy.js.
There is also a Gemooy article on the esowiki which contains the description, some example programs, and a Turing-completeness proof.