protected override Expression DoResolve(ResolveContext rc)
{
if (rc.IsRuntimeBinder)
{
if (UnwrapLeft == null && !Left.Type.IsNullableType)
{
Left = Wrap.Create(Left, rc.Module.PredefinedTypes.Nullable.TypeSpec.MakeGenericType(rc.Module, new[] { Left.Type }));
}
if (UnwrapRight == null && !Right.Type.IsNullableType)
{
Right = Wrap.Create(Right, rc.Module.PredefinedTypes.Nullable.TypeSpec.MakeGenericType(rc.Module, new[] { Right.Type }));
}
}
else
{
if (UnwrapLeft == null && Left != null && Left.Type.IsNullableType)
{
Left = Unwrap.CreateUnwrapped(Left);
UnwrapLeft = Left as Unwrap;
}
if (UnwrapRight == null && Right != null && Right.Type.IsNullableType)
{
Right = Unwrap.CreateUnwrapped(Right);
UnwrapRight = Right as Unwrap;
}
}
type = Binary.Type;
eclass = Binary.eclass;
return(this);
}
protected override Expression DoResolve(ResolveContext ec)
{
//
// It's null when lifting non-nullable type
//
if (unwrap == null) {
// S -> T? is wrap only
if (type.IsNullableType)
return Wrap.Create (expr, type);
// S -> T can be simplified
return expr;
}
// Wrap target for T?
if (type.IsNullableType) {
if (!expr.Type.IsNullableType) {
expr = Wrap.Create (expr, type);
if (expr == null)
return null;
}
null_value = LiftedNull.Create (type, loc);
} else if (TypeSpec.IsValueType (type)) {
null_value = LiftedNull.Create (type, loc);
} else {
null_value = new NullConstant (type, loc);
}
eclass = ExprClass.Value;
return this;
}
Expression LiftOperand(ResolveContext rc, Expression expr)
{
TypeSpec type;
if (expr.IsNull) {
type = Left.IsNull ? Right.Type : Left.Type;
} else {
type = expr.Type;
}
if (!type.IsNullableType)
type = NullableInfo.MakeType (rc.Module, type);
return Wrap.Create (expr, type);
}
Expression LiftOperand(ResolveContext rc, Expression expr)
{
TypeSpec type;
if (expr.IsNull)
{
type = Left.IsNull ? Right.Type : Left.Type;
}
else
{
type = expr.Type;
}
if (!type.IsNullableType)
{
type = rc.Module.PredefinedTypes.Nullable.TypeSpec.MakeGenericType(rc.Module, new[] { type });
}
return(Wrap.Create(expr, type));
}
public override Expression DoResolve(EmitContext ec)
{
wrap = Wrap.Create(expr, type);
if (wrap == null)
{
return(null);
}
//
// It's null when lifted conversion is transparent
//
if (unwrap == null)
{
return(wrap);
}
null_value = LiftedNull.Create(type, loc);
eclass = ExprClass.Value;
return(this);
}
public override Expression DoResolve(ResolveContext ec)
{
//
// It's null when lifting non-nullable type
//
if (unwrap == null)
{
// S -> T? is wrap only
if (TypeManager.IsNullableType(type))
{
return(Wrap.Create(expr, type));
}
// S -> T can be simplified
return(expr);
}
// Wrap target for T?
if (TypeManager.IsNullableType(type))
{
expr = Wrap.Create(expr, type);
if (expr == null)
{
return(null);
}
null_value = LiftedNull.Create(type, loc);
}
else
{
null_value = new NullLiteral(type, loc);
}
eclass = ExprClass.Value;
return(this);
}