content: /*******************************************************************************
  * Copyright (c) 2009 Luaj.org. All rights reserved.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
  *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
  * 
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  ******************************************************************************/
  package org.luaj.vm2.lib;
  
  //TODO 与3.0不一样
  
  import org.luaj.vm2.LuaTable;
  import org.luaj.vm2.LuaValue;
  import org.luaj.vm2.Varargs;
  
  /** 
   * Subclass of {@link LibFunction} which implements the lua standard {@code table} 
   * library. 
   * 
   * <p>
   * Typically, this library is included as part of a call to either 
   * {@link JsePlatform#standardGlobals()} or {@link JmePlatform#standardGlobals()}
   * <pre> {@code
   * Globals globals = JsePlatform.standardGlobals();
   * System.out.println( globals.get("table").get("length").call( LuaValue.tableOf() ) );
   * } </pre>
   * <p>
   * To instantiate and use it directly, 
   * link it into your globals table via {@link LuaValue#load(LuaValue)} using code such as:
   * <pre> {@code
   * Globals globals = new Globals();
   * globals.load(new JseBaseLib());
   * globals.load(new PackageLib());
   * globals.load(new TableLib());
   * System.out.println( globals.get("table").get("length").call( LuaValue.tableOf() ) );
   * } </pre>
   * <p>
   * This has been implemented to match as closely as possible the behavior in the corresponding library in C.
   * @see LibFunction
   * @see JsePlatform
   * @see JmePlatform
   * @see <a href="http://www.lua.org/manual/5.2/manual.html#6.5">Lua 5.2 Table Lib Reference</a>
   */
  public class TableLib extends TwoArgFunction {
  
  	public LuaValue call(LuaValue modname, LuaValue env) {
  		LuaTable table = new LuaTable();
  		table.set("concat", new concat());
  		table.set("insert", new insert());
  		table.set("pack", new pack());
  		table.set("remove", new remove());
  		table.set("sort", new sort());
  		table.set("unpack", new unpack());
          table.set("getn", new getn());//TODO yesong添加的函数
  		env.set("table", table);
  		env.get("package").get("loaded").set("table", table);
  		return NIL;
  	}
  
  	static class TableLibFunction extends LibFunction {
  		public LuaValue call() {
  			return argerror(1, "table expected, got no value");
  		}
  	}
  	
  	// "concat" (table [, sep [, i [, j]]]) -> string
  	static class concat extends TableLibFunction {
  		public LuaValue call(LuaValue list) {
  			return list.checktable().concat(EMPTYSTRING,1,list.length());
  		}
  		public LuaValue call(LuaValue list, LuaValue sep) {
  			return list.checktable().concat(sep.checkstring(),1,list.length());
  		}
  		public LuaValue call(LuaValue list, LuaValue sep, LuaValue i) {
  			return list.checktable().concat(sep.checkstring(),i.checkint(),list.length());
  		}
  		public LuaValue call(LuaValue list, LuaValue sep, LuaValue i, LuaValue j) {
  			return list.checktable().concat(sep.checkstring(),i.checkint(),j.checkint());
  		}
  	}
  
  	// "insert" (table, [pos,] value) -> prev-ele
  	static class insert extends TableLibFunction {
  		public LuaValue call(LuaValue list) {
  			return argerror(2, "value expected");
  		}
  		public LuaValue call(LuaValue table, LuaValue value) {
  			table.checktable().insert(table.length()+1,value);
  			return NONE;
  		}
  		public LuaValue call(LuaValue table, LuaValue pos, LuaValue value) {
  			table.checktable().insert(pos.checkint(),value);
  			return NONE;
  		}
  	}
  	
  	// "pack" (...) -> table
  	static class pack extends VarArgFunction {
  		public Varargs invoke(Varargs args) {
  			LuaValue t = tableOf(args, 1);
  			t.set("n", args.narg());
  			return t;
  		}
  	}
  
  	// "remove" (table [, pos]) -> removed-ele
  	static class remove extends TableLibFunction {
  		public LuaValue call(LuaValue list) {
  			return list.checktable().remove(0);
  		}
  		public LuaValue call(LuaValue list, LuaValue pos) {
  			return list.checktable().remove(pos.checkint());
  		}
  	}
  
  	// "sort" (table [, comp])
  	static class sort extends TwoArgFunction {
  		public LuaValue call(LuaValue table, LuaValue compare) {
  			table.checktable().sort(compare.isnil()? NIL: compare.checkfunction());
  			return NONE;
  		}
  	}
  
  	// "unpack", // (list [,i [,j]]) -> result1, ...
  	static class unpack extends VarArgFunction {
  		public Varargs invoke(Varargs args) {
  			LuaTable t = args.checktable(1);
  			switch (args.narg()) {
  			case 1: return t.unpack();
  			case 2: return t.unpack(args.checkint(2));
  			default: return t.unpack(args.checkint(2), args.checkint(3));
  			}
  		}
  	}
  
      // "getn" (...) -> int
      static class getn extends TableLibFunction {
          public LuaValue call(LuaValue list) {
              return list.checktable().len();
          }
      }
  }
  