PAKCS is an implementation of the multi-paradigm declarative language Curry jointly developed by the Portland State University, the Aachen University of Technology, and the University of Kiel. Although this is not a highly optimized implementation but based on a high-level compilation of Curry programs into Prolog programs, it is not a toy implementation: PAKCS has been used for a variety of applications (e.g., graphical programming environments, an object-oriented front-end for Curry, partial evaluators, database applications, HTML programming with dynamic web pages, prototyping embedded systems). The size of all current Curry applications implemented with PAKCS amounts to more than 150,000 lines (or 8 mbytes) of program code.
There is a manual (PDF) which describes the use of the system and the minor restrictions of PAKCS compared to Curry. Since this document compares only PAKCS to Curry, you may have a look at the Curry report which describes the full language.
You can download the PAKCS distribution here. Alternatively, you can also run your Curry program using Smap, a web-based interactive environment to execute Curry programs with PAKCS (and other systems). Note that there is time limit for the execution of Curry programs and some predefined system functions (like reading/writing files) are not available due to security reasons.
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