The BPL system we are presenting is a prototype, high level implementation written on top of SWI-Prolog [8]. The complete implementation consists of about 900 lines of Prolog code. The parser and translator module translates (compiles) rules and facts of the source BPL code into an intermediate Prolog code representation which is called ``TPL code'' (Translated BPL code). Then, following standard techniques [7], a meta-interpreter executes the TPL code according to the weak SLD resolution principle.
More information about the structure and main features of the BPL system can be found by [downloading] the paper [3].