一教学目的简单的Prolog解释器

Overview PrettyProlog is a simple Prolog interpreter with the ability to graphically show the resolution process (visualize stack and SLD tree, solve step-by-step), written in Java and suitable for use in education. It supports a few Prolog datatypes (besides the obvious constants and functors, lists, character strings and floating-point numbers are supported, though there are no built-in predicates that operate on them), a few useful system predicates, and the cut operator. System predicates can be written in Java and integrated in the system with a Prolog directive. There is limited support for infix operators (only arity 2, no precedence rules supported), and new infix operators can be added dynamically by the user. PrettyProlog was originally developed by Alessio Stalla for his bachelor"s degree thesis in 2006 and described in the following paper: http://www.disi.