org.luaj.vm2.lib
Class PackageLib.require

java.lang.Object
  extended by org.luaj.vm2.Varargs
      extended by org.luaj.vm2.LuaValue
          extended by org.luaj.vm2.LuaFunction
              extended by org.luaj.vm2.lib.LibFunction
                  extended by org.luaj.vm2.lib.OneArgFunction
                      extended by org.luaj.vm2.lib.PackageLib.require
Enclosing class:
PackageLib

public class PackageLib.require
extends OneArgFunction

require (modname) Loads the given module. The function starts by looking into the package.loaded table to determine whether modname is already loaded. If it is, then require returns the value stored at package.loaded[modname]. Otherwise, it tries to find a loader for the module. To find a loader, require is guided by the package.searchers sequence. By changing this sequence, we can change how require looks for a module. The following explanation is based on the default configuration for package.searchers. First require queries package.preload[modname]. If it has a value, this value (which should be a function) is the loader. Otherwise require searches for a Lua loader using the path stored in package.path. If that also fails, it searches for a Java loader using the classpath, using the public default constructor, and casting the instance to LuaFunction. Once a loader is found, require calls the loader with two arguments: modname and an extra value dependent on how it got the loader. If the loader came from a file, this extra value is the file name. If the loader is a Java instance of LuaFunction, this extra value is the environment. If the loader returns any non-nil value, require assigns the returned value to package.loaded[modname]. If the loader does not return a non-nil value and has not assigned any value to package.loaded[modname], then require assigns true to this entry. In any case, require returns the final value of package.loaded[modname]. If there is any error loading or running the module, or if it cannot find any loader for the module, then require raises an error.


Field Summary
 
Fields inherited from class org.luaj.vm2.lib.LibFunction
name, opcode
 
Fields inherited from class org.luaj.vm2.LuaFunction
s_metatable
 
Fields inherited from class org.luaj.vm2.LuaValue
ADD, CALL, CONCAT, DIV, EMPTYSTRING, ENV, EQ, FALSE, INDEX, LE, LEN, LT, METATABLE, MINUSONE, MOD, MODE, MUL, NEWINDEX, NIL, NILS, NONE, NOVALS, ONE, POW, SUB, TBOOLEAN, TFUNCTION, TINT, TLIGHTUSERDATA, TNIL, TNONE, TNUMBER, TOSTRING, TRUE, TSTRING, TTABLE, TTHREAD, TUSERDATA, TVALUE, TYPE_NAMES, UNM, ZERO
 
Constructor Summary
PackageLib.require()
           
 
Method Summary
 LuaValue call(LuaValue arg)
          Call this with 1 argument, including metatag processing, and return only the first return value.
 
Methods inherited from class org.luaj.vm2.lib.OneArgFunction
call, call, call, invoke
 
Methods inherited from class org.luaj.vm2.lib.LibFunction
bind, bind, call, newupe, newupl, newupn, tojstring
 
Methods inherited from class org.luaj.vm2.LuaFunction
checkfunction, classnamestub, getmetatable, isfunction, name, optfunction, strvalue, type, typename
 
Methods inherited from class org.luaj.vm2.LuaValue
add, add, add, and, arg, arg1, argerror, argerror, aritherror, aritherror, arithmt, arithmtwith, assert_, buffer, call, callmt, checkboolean, checkclosure, checkdouble, checkglobals, checkint, checkinteger, checkjstring, checklong, checkmetatag, checknotnil, checknumber, checknumber, checkstring, checktable, checkthread, checkuserdata, checkuserdata, compareerror, compareerror, comparemt, concat, concat, concatmt, concatTo, concatTo, concatTo, div, div, div, divInto, eq_b, eq, eqmtcall, equals, error, get, get, get, gettable, gt_b, gt_b, gt_b, gt, gt, gt, gteq_b, gteq_b, gteq_b, gteq, gteq, gteq, illegal, inext, initupvalue1, invoke, invoke, invoke, invoke, invoke, invokemethod, invokemethod, invokemethod, invokemethod, invokemethod, invokemethod, isboolean, isclosure, isint, isinttype, islong, isnil, isnumber, isstring, istable, isthread, isuserdata, isuserdata, isvalidkey, len, lenerror, length, listOf, listOf, load, lt_b, lt_b, lt_b, lt, lt, lt, lteq_b, lteq_b, lteq_b, lteq, lteq, lteq, metatableOf, metatag, method, method, method, method, method, method, mod, mod, mod, modFrom, mul, mul, mul, narg, neg, neq_b, neq, next, not, onInvoke, optboolean, optclosure, optdouble, optint, optinteger, optjstring, optlong, optnumber, optstring, opttable, optthread, optuserdata, optuserdata, optvalue, or, pow, pow, pow, powWith, powWith, presize, raweq, raweq, raweq, raweq, raweq, rawget, rawget, rawget, rawlen, rawset, rawset, rawset, rawset, rawset, rawset, rawset, rawsetlist, set, set, set, set, set, set, set, setmetatable, settable, strcmp, strcmp, strongvalue, sub, sub, sub, subargs, subFrom, subFrom, tableOf, tableOf, tableOf, tableOf, tableOf, tableOf, tailcallOf, testfor_b, toboolean, tobyte, tochar, todouble, tofloat, toint, tolong, tonumber, toshort, tostring, toString, touserdata, touserdata, typerror, unimplemented, userdataOf, userdataOf, valueOf, valueOf, valueOf, valueOf, valueOf, valueOf, varargsOf, varargsOf, varargsOf, varargsOf, varargsOf, varargsOf
 
Methods inherited from class org.luaj.vm2.Varargs
argcheck, checkboolean, checkclosure, checkdouble, checkfunction, checkint, checkinteger, checkjstring, checklong, checknotnil, checknumber, checkstring, checktable, checkthread, checkuserdata, checkuserdata, checkvalue, eval, isfunction, isnil, isnoneornil, isnumber, isstring, istable, isTailcall, isthread, isuserdata, isvalue, optboolean, optclosure, optdouble, optfunction, optint, optinteger, optjstring, optlong, optnumber, optstring, opttable, optthread, optuserdata, optuserdata, optvalue, toboolean, tobyte, tochar, todouble, tofloat, toint, tojstring, tolong, toshort, touserdata, touserdata, type
 
Methods inherited from class java.lang.Object
clone, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Constructor Detail

PackageLib.require

public PackageLib.require()
Method Detail

call

public LuaValue call(LuaValue arg)
Description copied from class: LuaValue
Call this with 1 argument, including metatag processing, and return only the first return value.

If this is a LuaFunction, call it, and return only its first return value, dropping any others. Otherwise, look for the LuaValue.CALL metatag and call that.

If the return value is a Varargs, only the 1st value will be returned. To get multiple values, use LuaValue.invoke() instead.

To call this as a method call, use LuaValue.method(LuaValue) instead.

Specified by:
call in class OneArgFunction
Parameters:
arg - First argument to supply to the called function
Returns:
First return value (this(arg)), or LuaValue.NIL if there were none.
See Also:
LuaValue.call(), LuaValue.call(LuaValue,LuaValue), LuaValue.call(LuaValue, LuaValue, LuaValue), LuaValue.invoke(Varargs), LuaValue.method(String,LuaValue), LuaValue.method(LuaValue,LuaValue)


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