org.luaj.vm2.lib.TableLib Maven / Gradle / Ivy
Show all versions of luaj-jse Show documentation
/*******************************************************************************
* 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;
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.
*
*
* Typically, this library is included as part of a call to either
* {@link JsePlatform#standardGlobals()} or {@link JmePlatform#standardGlobals()}
*
* To instantiate and use it directly,
* link it into your globals table via {@link LuaValue#load(LuaValue)} using code such as:
*
{@code
* LuaTable _G = new LuaTable();
* LuaThread.setGlobals(_G);
* _G.load(new BaseLib());
* _G.load(new PackageLib());
* _G.load(new TableLib());
* LuaValue tbl = LuaValue.listOf( new LuaValue[] {
* LuaValue.valueOf( "abc" ),
* LuaValue.valueOf( "def" ) } );
* LuaValue sep = LuaValue.valueOf( "-" );
* System.out.println( _G.get("table").get("concat").call( tbl, sep ) );
* }
* Doing so will ensure the library is properly initialized
* and loaded into the globals table.
*
* 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 http://www.lua.org/manual/5.1/manual.html#5.5
*/
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());
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));
}
}
}
}