public override bool Equals(Object x)
{
if (!(x is SeqValue))
{
return(false);
}
IteratorValue e1 = GetIterator();
IteratorValue e2 = (x as SeqValue).GetIterator();
bool b1 = e1.MoveNext();
bool b2 = e2.MoveNext();
// While both lists have data.
while (b1 && b2)
{
HeronValue v1 = e1.GetValue();
HeronValue v2 = e2.GetValue();
if (!v1.Equals(v2))
{
return(false);
}
b1 = e1.MoveNext();
b2 = e2.MoveNext();
}
// If one of b1 or b2 is true, then we didn't get to the end of list
// so we have different sized lists.
if (b1 || b2)
{
return(false);
}
return(true);
}
public override HeronValue Eval(VM vm)
{
HeronValue a = operand1.Eval(vm);
HeronValue b = operand2.Eval(vm);
switch (opcode)
{
case OpCode.opEq:
return(new BoolValue(a.Equals(b)));
case OpCode.opNEq:
return(new BoolValue(!a.Equals(b)));
case OpCode.opIs:
{
TypeValue tv = b as TypeValue;
if (tv == null)
{
throw new Exception("The second argument of the 'is' operator must be a type");
}
return(new BoolValue(a.Is(tv.Type)));
}
case OpCode.opAs:
{
HeronType t = b as HeronType;
if (t == null)
{
throw new Exception("The 'as' operator expects a type as a right hand argument");
}
HeronValue r = a.As(t);
if (r != null)
{
return(r);
}
if (t is InterfaceDefn && a is ClassInstance)
{
DuckValue dv = new DuckValue(a as ClassInstance, t as InterfaceDefn);
return(dv);
}
throw new Exception("Failed to convert " + a.Type.name + " to a " + t.name);
};
}
return(a.InvokeBinaryOperator(vm, opcode, b));
}
public override void Eval(VM vm)
{
HeronValue o = condition.Eval(vm);
foreach (CaseStatement c in cases)
{
HeronValue cond = vm.Eval(c.condition);
if (o.Equals(cond))
{
vm.Eval(c.statement);
return;
}
}
if (ondefault != null)
{
vm.Eval(ondefault);
}
}
static public void TestCompareValues(string sInput, string sOutput)
{
Console.WriteLine("testing evaluation of " + sInput);
Console.WriteLine("expecting result of " + sOutput);
try
{
HeronValue input = vm.EvalString(sInput);
HeronValue output = vm.EvalString(sOutput);
Console.WriteLine("test input was " + input.ToString());
Console.WriteLine("test output was " + output.ToString());
if (!input.Equals(output))
{
throw new Exception("Result was different than expected");
}
}
catch (Exception e)
{
Console.WriteLine("test failed with exception " + e.Message);
}
}