public static JsValue Compare(JsValue x, JsValue y, bool leftFirst = true)
{
JsValue px, py;
if (leftFirst)
{
px = TypeConverter.ToPrimitive(x, Types.Number);
py = TypeConverter.ToPrimitive(y, Types.Number);
}
else
{
py = TypeConverter.ToPrimitive(y, Types.Number);
px = TypeConverter.ToPrimitive(x, Types.Number);
}
var typea = px.Type;
var typeb = py.Type;
if (typea != Types.String || typeb != Types.String)
{
var nx = TypeConverter.ToNumber(px);
var ny = TypeConverter.ToNumber(py);
if (double.IsNaN(nx) || double.IsNaN(ny))
{
return(Undefined.Instance);
}
if (nx.Equals(ny))
{
return(false);
}
if (double.IsPositiveInfinity(nx))
{
return(false);
}
if (double.IsPositiveInfinity(ny))
{
return(true);
}
if (double.IsNegativeInfinity(ny))
{
return(false);
}
if (double.IsNegativeInfinity(nx))
{
return(true);
}
return(nx < ny);
}
else
{
return(String.CompareOrdinal(TypeConverter.ToString(x), TypeConverter.ToString(y)) < 0);
}
}
public static bool Equal(JsValue x, JsValue y)
{
var typex = x.Type;
var typey = y.Type;
if (typex == typey)
{
return(StrictlyEqual(x, y));
}
if (x == Null.Instance && y == Undefined.Instance)
{
return(true);
}
if (x == Undefined.Instance && y == Null.Instance)
{
return(true);
}
if (typex == Types.Number && typey == Types.String)
{
return(Equal(x, TypeConverter.ToNumber(y)));
}
if (typex == Types.String && typey == Types.Number)
{
return(Equal(TypeConverter.ToNumber(x), y));
}
if (typex == Types.Boolean)
{
return(Equal(TypeConverter.ToNumber(x), y));
}
if (typey == Types.Boolean)
{
return(Equal(x, TypeConverter.ToNumber(y)));
}
if (typey == Types.Object && (typex == Types.String || typex == Types.Number))
{
return(Equal(x, TypeConverter.ToPrimitive(y)));
}
if (typex == Types.Object && (typey == Types.String || typey == Types.Number))
{
return(Equal(TypeConverter.ToPrimitive(x), y));
}
return(false);
}
public JsValue EvaluateAssignmentExpression(AssignmentExpression assignmentExpression)
{
var lref = EvaluateExpression(assignmentExpression.Left) as Reference;
JsValue rval = _engine.GetValue(EvaluateExpression(assignmentExpression.Right));
if (lref == null)
{
throw new JavaScriptException(_engine.ReferenceError);
}
if (assignmentExpression.Operator == AssignmentOperator.Assign) // "="
{
if (lref.IsStrict() && lref.GetBase().TryCast <EnvironmentRecord>() != null && (lref.GetReferencedName() == "eval" || lref.GetReferencedName() == "arguments"))
{
throw new JavaScriptException(_engine.SyntaxError);
}
_engine.PutValue(lref, rval);
return(rval);
}
JsValue lval = _engine.GetValue(lref);
switch (assignmentExpression.Operator)
{
case AssignmentOperator.PlusAssign:
var lprim = TypeConverter.ToPrimitive(lval);
var rprim = TypeConverter.ToPrimitive(rval);
if (lprim.IsString() || rprim.IsString())
{
lval = TypeConverter.ToString(lprim) + TypeConverter.ToString(rprim);
}
else
{
lval = TypeConverter.ToNumber(lprim) + TypeConverter.ToNumber(rprim);
}
break;
case AssignmentOperator.MinusAssign:
lval = TypeConverter.ToNumber(lval) - TypeConverter.ToNumber(rval);
break;
case AssignmentOperator.TimesAssign:
if (lval == Undefined.Instance || rval == Undefined.Instance)
{
lval = Undefined.Instance;
}
else
{
lval = TypeConverter.ToNumber(lval) * TypeConverter.ToNumber(rval);
}
break;
case AssignmentOperator.DivideAssign:
lval = Divide(lval, rval);
break;
case AssignmentOperator.ModuloAssign:
if (lval == Undefined.Instance || rval == Undefined.Instance)
{
lval = Undefined.Instance;
}
else
{
lval = TypeConverter.ToNumber(lval) % TypeConverter.ToNumber(rval);
}
break;
case AssignmentOperator.BitwiseAndAssign:
lval = TypeConverter.ToInt32(lval) & TypeConverter.ToInt32(rval);
break;
case AssignmentOperator.BitwiseOrAssign:
lval = TypeConverter.ToInt32(lval) | TypeConverter.ToInt32(rval);
break;
case AssignmentOperator.BitwiseXOrAssign:
lval = TypeConverter.ToInt32(lval) ^ TypeConverter.ToInt32(rval);
break;
case AssignmentOperator.LeftShiftAssign:
lval = TypeConverter.ToInt32(lval) << (int)(TypeConverter.ToUint32(rval) & 0x1F);
break;
case AssignmentOperator.RightShiftAssign:
lval = TypeConverter.ToInt32(lval) >> (int)(TypeConverter.ToUint32(rval) & 0x1F);
break;
case AssignmentOperator.UnsignedRightShiftAssign:
lval = (uint)TypeConverter.ToInt32(lval) >> (int)(TypeConverter.ToUint32(rval) & 0x1F);
break;
default:
throw new NotImplementedException();
}
_engine.PutValue(lref, lval);
return(lval);
}
public JsValue EvaluateBinaryExpression(BinaryExpression expression)
{
var leftExpression = EvaluateExpression(expression.Left);
JsValue left = _engine.GetValue(leftExpression);
var rightExpression = EvaluateExpression(expression.Right);
JsValue right = _engine.GetValue(rightExpression);
JsValue value;
switch (expression.Operator)
{
case BinaryOperator.Plus:
var lprim = TypeConverter.ToPrimitive(left);
var rprim = TypeConverter.ToPrimitive(right);
if (lprim.IsString() || rprim.IsString())
{
value = TypeConverter.ToString(lprim) + TypeConverter.ToString(rprim);
}
else
{
value = TypeConverter.ToNumber(lprim) + TypeConverter.ToNumber(rprim);
}
break;
case BinaryOperator.Minus:
value = TypeConverter.ToNumber(left) - TypeConverter.ToNumber(right);
break;
case BinaryOperator.Times:
if (left == Undefined.Instance || right == Undefined.Instance)
{
value = Undefined.Instance;
}
else
{
value = TypeConverter.ToNumber(left) * TypeConverter.ToNumber(right);
}
break;
case BinaryOperator.Divide:
value = Divide(left, right);
break;
case BinaryOperator.Modulo:
if (left == Undefined.Instance || right == Undefined.Instance)
{
value = Undefined.Instance;
}
else
{
value = TypeConverter.ToNumber(left) % TypeConverter.ToNumber(right);
}
break;
case BinaryOperator.Equal:
value = Equal(left, right);
break;
case BinaryOperator.NotEqual:
value = !Equal(left, right);
break;
case BinaryOperator.Greater:
value = Compare(right, left, false);
if (value == Undefined.Instance)
{
value = false;
}
break;
case BinaryOperator.GreaterOrEqual:
value = Compare(left, right);
if (value == Undefined.Instance || value.AsBoolean())
{
value = false;
}
else
{
value = true;
}
break;
case BinaryOperator.Less:
value = Compare(left, right);
if (value == Undefined.Instance)
{
value = false;
}
break;
case BinaryOperator.LessOrEqual:
value = Compare(right, left, false);
if (value == Undefined.Instance || value.AsBoolean())
{
value = false;
}
else
{
value = true;
}
break;
case BinaryOperator.StrictlyEqual:
return(StrictlyEqual(left, right));
case BinaryOperator.StricltyNotEqual:
return(!StrictlyEqual(left, right));
case BinaryOperator.BitwiseAnd:
return(TypeConverter.ToInt32(left) & TypeConverter.ToInt32(right));
case BinaryOperator.BitwiseOr:
return(TypeConverter.ToInt32(left) | TypeConverter.ToInt32(right));
case BinaryOperator.BitwiseXOr:
return(TypeConverter.ToInt32(left) ^ TypeConverter.ToInt32(right));
case BinaryOperator.LeftShift:
return(TypeConverter.ToInt32(left) << (int)(TypeConverter.ToUint32(right) & 0x1F));
case BinaryOperator.RightShift:
return(TypeConverter.ToInt32(left) >> (int)(TypeConverter.ToUint32(right) & 0x1F));
case BinaryOperator.UnsignedRightShift:
return((uint)TypeConverter.ToInt32(left) >> (int)(TypeConverter.ToUint32(right) & 0x1F));
case BinaryOperator.InstanceOf:
var f = right.TryCast <FunctionInstance>();
if (f == null)
{
throw new JavaScriptException(_engine.TypeError, "instanceof can only be used with a function object");
}
value = f.HasInstance(left);
break;
case BinaryOperator.In:
if (!right.IsObject())
{
throw new JavaScriptException(_engine.TypeError, "in can only be used with an object");
}
value = right.AsObject().HasProperty(TypeConverter.ToString(left));
break;
default:
throw new NotImplementedException();
}
return(value);
}
