PrologShell.java

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import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import edu.tum.cs.prolog.PrologKnowledgeBase;

public class PrologShell {

        public static void main(String[] args) {
                System.out.println("\n"+
                                "The Simple yProlog Interactive Shell\n\n" +
                                "usage:\n" +
                                "      tell:  parent(eve, abel).\n" +
                                "             female(eve).\n" +
                                "             mother(X,Y) :- parent(X,Y), female(X).\n" +
                                "       ask:  mother(eve, abel)\n" +
                                "             mother(eve, X)\n" +
                                "   consult:  consult myfile.pl\n" +
                                "      exit:  exit\n"
                        );
                
                PrologKnowledgeBase kb = new PrologKnowledgeBase();
                BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
                String constant = "\\s*([a-z]\\w*|[0-9]+)\\s*";
                Pattern patGroundAtom = Pattern.compile(String.format("\\w+\\(%s(,%s)*\\)", constant, constant));
                for(;;) {
                        
                        try {
                                // get input query from stdin
                                System.out.print("\n> ");
                                String input = br.readLine().trim();

                                if(input.equalsIgnoreCase("exit"))
                                        break;

                                // parse expression...
                                if(input.startsWith("consult")) {
                                        String filename = input.substring(7).trim();
                                        System.out.printf("consulting %s\n", filename);
                                        kb.consultFile(filename);
                                }                               
                                else if(input.endsWith("."))
                                        kb.tell(input);
                                else {  
                                        Matcher m = patGroundAtom.matcher(input);
                                        if(m.matches()) {
                                                boolean result = kb.ask(input);
                                                System.out.println(result ? "Yes" : "No");
                                        }
                                        else {
                                                for(String atom : kb.fetchAtoms(input)) {
                                                        System.out.println(atom);
                                                }                                               
                                        }
                                }
                        }
                        catch (IOException e) {
                                System.err.println(e.getMessage());
                        }
                        catch (java.lang.Exception e) {
                                System.out.println(e.getMessage());
                        }
                }
        }
}

---

srldb
Author(s): Dominik Jain, Stefan Waldherr, Moritz Tenorth
autogenerated on Fri Jan 11 09:58:29 2013