private static Tuple<double, double> GetNumericOperatorParameters(ScriptProcessor processor, SObject left, SObject right)
{
double numLeft, numRight;
if (left is SNumber)
numLeft = ((SNumber)left).Value;
else
numLeft = left.ToNumber(processor).Value;
if (right is SNumber)
numRight = ((SNumber)right).Value;
else
numRight = right.ToNumber(processor).Value;
return new Tuple<double, double>(numLeft, numRight);
}
/// <summary>
/// Compares two objects for equality, converting types if needed.
/// </summary>
/// <remarks>Used by the == and != equality operators.</remarks>
public static bool LooseEquals(ScriptProcessor processor, SObject left, SObject right)
{
left = SObject.Unbox(left);
right = SObject.Unbox(right);
// both types are the same:
if (left.TypeOf() == right.TypeOf())
{
// If they are undefined or null, return true:
if (left.TypeOf() == SObject.LITERAL_UNDEFINED || left.TypeOf() == SObject.LITERAL_NULL)
{
return true;
}
// Both are numbers:
else if (left.TypeOf() == SObject.LITERAL_TYPE_NUMBER)
{
double numLeft = ((SNumber)left).Value;
double numRight = ((SNumber)right).Value;
return numLeft == numRight;
}
// Both are string:
else if (left.TypeOf() == SObject.LITERAL_TYPE_STRING)
{
string strLeft = ((SString)left).Value;
string strRight = ((SString)right).Value;
return strLeft == strRight;
}
// Both are bool:
else if (left.TypeOf() == SObject.LITERAL_TYPE_BOOL)
{
bool boolLeft = ((SBool)left).Value;
bool boolRight = ((SBool)right).Value;
return boolLeft == boolRight;
}
else
{
return ReferenceEquals(left, right);
}
}
// null & undefined
else if (left.TypeOf() == SObject.LITERAL_NULL && right.TypeOf() == SObject.LITERAL_UNDEFINED ||
left.TypeOf() == SObject.LITERAL_UNDEFINED && right.TypeOf() == SObject.LITERAL_NULL)
{
return true;
}
// When one is a number and another is a string, convert the string to a number and compare:
else if (left.TypeOf() == SObject.LITERAL_TYPE_STRING && right.TypeOf() == SObject.LITERAL_TYPE_NUMBER)
{
double numLeft = left.ToNumber(processor).Value;
double numRight = ((SNumber)right).Value;
return numLeft == numRight;
}
else if (left.TypeOf() == SObject.LITERAL_TYPE_NUMBER && right.TypeOf() == SObject.LITERAL_TYPE_STRING)
{
double numRight = right.ToNumber(processor).Value;
double numLeft = ((SNumber)left).Value;
return numLeft == numRight;
}
else if (left.TypeOf() == SObject.LITERAL_TYPE_BOOL)
{
return LooseEquals(processor, left.ToNumber(processor), right);
}
else if (right.TypeOf() == SObject.LITERAL_TYPE_BOOL)
{
return LooseEquals(processor, left, right.ToNumber(processor));
}
else
{
return false;
}
}
/// <summary>
/// Multiplies an object with -1.
/// </summary>
internal static SObject NegateNumber(ScriptProcessor processor, SObject obj)
{
double number;
if (obj is SNumber)
number = ((SNumber)obj).Value;
else
number = obj.ToNumber(processor).Value;
return processor.CreateNumber(number * -1);
}