public override bool TryInvoke(InvokeBinder binder, object[] args, out object result)
{
for (var i = 0; i < args.Length; i++)
{
args[i] = LuaHelper.WrapObject(args[i], _state);
}
var func = GetMetaFunction("call");
if (func != null)
{
if (args.Length == 0)
{
result = new DynamicArray(func.Call(_table), _state);
}
else
{
result = new DynamicArray(func.Call(new object[] { _table }.Concat(args).ToArray()), _state);
}
return(true);
}
else
{
result = null;
return(false);
}
}
private void SetLuaMember(string name, object value)
{
var tmp = LuaHelper.WrapObject(value, Lua, name);
if (tmp != null) //if a function was registered tmp is null, but we dont want to nil the function :P
{
Lua[name] = tmp;
}
}
public dynamic Power(object operand)
{
operand = LuaHelper.WrapObject(operand, _state);
var func = GetMetaFunction("pow");
if (func != null)
{
return(func.Call(_table, operand));
}
throw new InvalidOperationException("Metamethod __pow not found");
}
private void SetTableMember(string name, object value)
{
var tmp = LuaHelper.WrapObject(value, _state, _path + "." + name);
if (tmp == null)
{
return;
}
var func = GetMetaFunction("newindex");
if (func != null)
{
func.Call(_table, name, value);
}
else
{
_table[name] = value;
}
}
public override bool TryBinaryOperation(BinaryOperationBinder binder, object arg, out object result)
{
string metamethodName;
var switchOperands = false; //Lua has only comparison metamethods for less, so for greater the we have to switch the operands
var negateResult = false; //Lua has only metamethods for equal, so we need this trick here.
switch (binder.Operation)
{
//Math
case ExpressionType.Add:
case ExpressionType.AddChecked:
case ExpressionType.AddAssign:
case ExpressionType.AddAssignChecked: //TODO: Thing about __concat
metamethodName = "add";
break;
case ExpressionType.Subtract:
case ExpressionType.SubtractChecked:
case ExpressionType.SubtractAssign:
case ExpressionType.SubtractAssignChecked:
metamethodName = "sub";
break;
case ExpressionType.Multiply:
case ExpressionType.MultiplyChecked:
case ExpressionType.MultiplyAssign:
case ExpressionType.MultiplyAssignChecked:
metamethodName = "mul";
break;
case ExpressionType.Divide:
case ExpressionType.DivideAssign:
metamethodName = "div";
break;
case ExpressionType.Modulo:
case ExpressionType.ModuloAssign:
metamethodName = "mod";
break;
case ExpressionType.Power:
case ExpressionType.PowerAssign:
metamethodName = "pow";
break;
//Logic Tests
case ExpressionType.Equal:
metamethodName = "eq";
break;
case ExpressionType.NotEqual:
metamethodName = "eq";
negateResult = true;
break;
case ExpressionType.GreaterThan:
metamethodName = "lt";
switchOperands = true;
break;
case ExpressionType.GreaterThanOrEqual:
metamethodName = "le";
switchOperands = true;
break;
case ExpressionType.LessThan:
metamethodName = "lt";
break;
case ExpressionType.LessThanOrEqual:
metamethodName = "le";
break;
default: //This operation is not supported by Lua...
result = null;
return(false);
}
var mtFunc = GetMetaFunction(metamethodName);
if (mtFunc == null)
{
result = null;
return(false);
}
if (!switchOperands)
{
//Metamethods just return one value, or the other will be ignored anyway
result = mtFunc.Call(_table, LuaHelper.WrapObject(arg, _state)) [0];
}
else
{
result = mtFunc.Call(LuaHelper.WrapObject(arg, _state), _table)[0];
}
//We can't negate if its not bool. If the metamethod returned someting other than bool and ~= is called there will be a bug. (But who would do this?)
if (negateResult && result is bool b)
{
result = !b;
}
return(true);
}
