The DoCon computer algebra system implements recently a good-sized piece of commutative algebra. One of the project aims is to test the efficiency of a real-world CA system based on pure functionality and "lazy" computation. Algebraic category hierarchy is expressed mostly by the Haskell type classes, domains - by class instances. But domains are also described by explicit expressions.

**Developer**:Sergey D. Mechveliani**Contact**:- Sergey Mechveliani 152020, Program Systems Institute, Pereslavl-Zalessky, Russia. e-mail: mechvel@botik.ru phone: +7(08535)98031

**Number of sites:**1**In use:**since September 1999**Language:**Haskell (Haskell-2-pre functional extension of Haskell-98 the last system version was tested under ghc-6.2.2, Linux).**Compilers:**Glasgow Haskell ghc-6.2.2**Availability:**the source program of the last version DoCon-2.08, and manual, can be copied from ftp, web, web.**Related publications:**- "Computer algebra with Haskell:
applying functional-categorial-`lazy' programming"
In Proceedings of International Workshop CAAP-2001, Dubna, Russia. hscaDub (40Kb)

- The Manual book in the archive of DoCon-2.08 distribution.
- Basic Algebra Proposal for Haskell Standard Library.

- "Computer algebra with Haskell:
applying functional-categorial-`lazy' programming"
**Note:**The manual describes certain tests for the performance comparison to the strict, non-functional CA system MuPAD and to the strict CA system Axiom on several tasks from mathematical practice.