/// <summary>
/// Compares two objects for equality, respecting their typings.
/// </summary>
/// <remarks>Used by the === and !== equality operators.</remarks>
public static bool StrictEquals(ScriptProcessor processor, SObject left, SObject right)
{
left = SObject.Unbox(left);
right = SObject.Unbox(right);
if (left.TypeOf() != right.TypeOf())
{
return(false);
}
// If they are undefined or null, return true:
if (left.TypeOf() == SObject.LiteralUndefined || left.TypeOf() == SObject.LiteralNull)
{
return(true);
}
// Both are numbers:
if (left.TypeOf() == SObject.LiteralTypeNumber)
{
var numLeft = ((SNumber)left).Value;
var numRight = ((SNumber)right).Value;
return(Math.Abs(numLeft - numRight) < double.Epsilon);
}
// Both are string:
if (left.TypeOf() == SObject.LiteralTypeString)
{
var strLeft = ((SString)left).Value;
var strRight = ((SString)right).Value;
return(strLeft == strRight);
}
// Both are bool:
if (left.TypeOf() == SObject.LiteralTypeBool)
{
var boolLeft = ((SBool)left).Value;
var boolRight = ((SBool)right).Value;
return(boolLeft == boolRight);
}
return(ReferenceEquals(left, right));
}
/// <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.LiteralUndefined || left.TypeOf() == SObject.LiteralNull)
{
return(true);
}
// Both are numbers:
if (left.TypeOf() == SObject.LiteralTypeNumber)
{
var numLeft = ((SNumber)left).Value;
var numRight = ((SNumber)right).Value;
return(Math.Abs(numLeft - numRight) < double.Epsilon);
}
// Both are string:
if (left.TypeOf() == SObject.LiteralTypeString)
{
var strLeft = ((SString)left).Value;
var strRight = ((SString)right).Value;
return(strLeft == strRight);
}
// Both are bool:
if (left.TypeOf() == SObject.LiteralTypeBool)
{
var boolLeft = ((SBool)left).Value;
var boolRight = ((SBool)right).Value;
return(boolLeft == boolRight);
}
return(ReferenceEquals(left, right));
}
// null & undefined
if (left.TypeOf() == SObject.LiteralNull && right.TypeOf() == SObject.LiteralUndefined ||
left.TypeOf() == SObject.LiteralUndefined && right.TypeOf() == SObject.LiteralNull)
{
return(true);
}
// When one is a number and another is a string, convert the string to a number and compare:
if (left.TypeOf() == SObject.LiteralTypeString && right.TypeOf() == SObject.LiteralTypeNumber)
{
var numLeft = left.ToNumber(processor).Value;
var numRight = ((SNumber)right).Value;
return(Math.Abs(numLeft - numRight) < double.Epsilon);
}
if (left.TypeOf() == SObject.LiteralTypeNumber && right.TypeOf() == SObject.LiteralTypeString)
{
var numRight = right.ToNumber(processor).Value;
var numLeft = ((SNumber)left).Value;
return(Math.Abs(numLeft - numRight) < double.Epsilon);
}
if (left.TypeOf() == SObject.LiteralTypeBool)
{
return(LooseEquals(processor, left.ToNumber(processor), right));
}
if (right.TypeOf() == SObject.LiteralTypeBool)
{
return(LooseEquals(processor, left, right.ToNumber(processor)));
}
return(false);
}