--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/luan/modules/PackageLib.java	Sun Jun 22 04:28:32 2014 +0000
@@ -0,0 +1,170 @@
+package luan.modules;
+
+import java.io.IOException;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+import luan.Luan;
+import luan.LuanState;
+import luan.LuanTable;
+import luan.LuanFunction;
+import luan.LuanJavaFunction;
+import luan.LuanElement;
+import luan.LuanException;
+
+
+public final class PackageLib {
+
+	private static final String jpath = "luan.modules.?Lib.LOADER";
+
+	public static final LuanFunction LOADER = new LuanFunction() {
+		@Override public Object call(LuanState luan,Object[] args) {
+			LuanTable module = new LuanTable();
+			module.put("loaded",luan.loaded());
+			module.put("preload",luan.preload());
+			module.put("path","?.luan;java:luan/modules/?.luan");
+			module.put("jpath",jpath);
+			try {
+				add( module, "require", LuanState.class, String.class );
+				add( module, "load_lib", String.class );
+				add( module, "search_path", String.class, String.class );
+				add( module, "search", LuanState.class, String.class );
+			} catch(NoSuchMethodException e) {
+				throw new RuntimeException(e);
+			}
+			LuanTable searchers = luan.searchers();
+			searchers.add(preloadSearcher);
+			searchers.add(fileSearcher);
+			searchers.add(javaSearcher);
+			module.put("searchers",searchers);
+			return module;
+		}
+	};
+
+	private static void add(LuanTable t,String method,Class<?>... parameterTypes) throws NoSuchMethodException {
+		t.put( method, new LuanJavaFunction(PackageLib.class.getMethod(method,parameterTypes),null) );
+	}
+
+	public static Object require(LuanState luan,String modName) throws LuanException {
+		LuanTable loaded = luan.loaded();
+		Object mod = loaded.get(modName);
+		if( mod == null ) {
+			Object[] a = search(luan,modName);
+			if( a == null )
+				throw luan.exception( "module '"+modName+"' not found" );
+			LuanFunction loader = (LuanFunction)a[0];
+			a[0] = modName;
+			mod = Luan.first(luan.call(loader,"<require \""+modName+"\">",a));
+			if( mod != null ) {
+				loaded.put(modName,mod);
+			} else {
+				mod = loaded.get(modName);
+				if( mod==null )
+					loaded.put(modName,true);
+			}
+		}
+		return mod;
+	}
+
+	public static Object[] search(LuanState luan,String modName) throws LuanException {
+		List<Object> list = null;
+		LuanTable searchers = (LuanTable)luan.get("Package.searchers");
+		if( searchers == null ) {
+			list = Collections.<Object>singletonList(javaSearcher);
+		} else {
+			list = searchers.asList();
+		}
+		for( Object s : list ) {
+			LuanFunction searcher = (LuanFunction)s;
+			Object[] a = Luan.array(luan.call(searcher,"<searcher>",new Object[]{modName}));
+			if( a.length >= 1 && a[0] instanceof LuanFunction )
+				return a;
+		}
+		return null;
+	}
+
+	public static final LuanFunction preloadSearcher = new LuanFunction() {
+		@Override public Object call(LuanState luan,Object[] args) {
+			String modName = (String)args[0];
+			return luan.preload().get(modName);
+		}
+	};
+
+	public static String search_path(String name,String path) {
+		name = name.replace('.','/');
+		for( String s : path.split(";") ) {
+			String file = s.replaceAll("\\?",name);
+			if( Utils.exists(file) )
+				return file;
+		}
+		return null;
+	}
+
+	public static final LuanFunction fileLoader = new LuanFunction() {
+		@Override public Object call(LuanState luan,Object[] args) throws LuanException {
+			String fileName = (String)args[1];
+			LuanFunction fn = BasicLib.load_file(luan,fileName);
+			return fn.call(luan,args);
+		}
+	};
+
+	public static final LuanFunction fileSearcher = new LuanFunction() {
+		@Override public Object[] call(LuanState luan,Object[] args) {
+			String modName = (String)args[0];
+			String path = (String)luan.get("Package.path");
+			if( path==null )
+				return LuanFunction.NOTHING;
+			String file = search_path(modName,path);
+			return file==null ? LuanFunction.NOTHING : new Object[]{fileLoader,file};
+		}
+	};
+
+
+	public static final LuanFunction javaLoader = new LuanFunction() {
+		@Override public Object call(LuanState luan,Object[] args) throws LuanException {
+			try {
+				String objName = (String)args[1];
+				LuanFunction fn = load_lib(objName);
+				return fn.call(luan,args);
+			} catch(ClassNotFoundException e) {
+				throw new RuntimeException(e);
+			} catch(NoSuchFieldException e) {
+				throw new RuntimeException(e);
+			} catch(IllegalAccessException e) {
+				throw new RuntimeException(e);
+			}
+		}
+	};
+
+	public static final LuanFunction javaSearcher = new LuanFunction() {
+		@Override public Object[] call(LuanState luan,Object[] args) {
+			String modName = (String)args[0];
+			String path = (String)luan.get("Package.jpath");
+			if( path==null )
+				path = jpath;
+			for( String s : path.split(";") ) {
+				String objName = s.replaceAll("\\?",modName);
+				try {
+					load_lib(objName);  // throws exception if not found
+					return new Object[]{javaLoader,objName};
+				} catch(ClassNotFoundException e) {
+				} catch(NoSuchFieldException e) {
+				} catch(IllegalAccessException e) {
+				}
+			}
+			return LuanFunction.NOTHING;
+		}
+	};
+
+
+	public static LuanFunction load_lib(String path)
+		throws ClassNotFoundException, NoSuchFieldException, IllegalAccessException
+	{
+		int i = path.lastIndexOf('.');
+		String clsPath = path.substring(0,i);
+		String fld = path.substring(i+1);
+		Class cls = Class.forName(clsPath);
+		return (LuanFunction)cls.getField(fld).get(null);
+	}
+
+}