/// <summary>
/// 暗黙のキャストを探す。
/// </summary>
private DynamicMetaObject DefferentType(DynamicMetaObject left, DynamicMetaObject right)
{
var val = TryCalcNumeric(left, right);
if (val != null)
{
return(val);
}
// 左辺のキャスト
var mInfo = BinderHelper.GetImplicitCast(left.LimitType, right.LimitType);
if (mInfo != null)
{
Expression expr = Expression.MakeBinary(this.Operation,
BinderHelper.Wrap(left.Expression, left.LimitType, right.LimitType),
Expression.Convert(right.Expression, right.LimitType));
return(new DynamicMetaObject(
BinderHelper.Wrap(expr, this.ReturnType),
BinderHelper.GetTypeRestriction(left, right)));
}
// 右辺のキャスト
mInfo = BinderHelper.GetImplicitCast(right.LimitType, left.LimitType);
if (mInfo != null)
{
Expression expr = Expression.MakeBinary(this.Operation,
Expression.Convert(left.Expression, left.LimitType),
BinderHelper.Wrap(right.Expression, right.LimitType, left.LimitType));
return(new DynamicMetaObject(
BinderHelper.Wrap(expr, this.ReturnType),
BinderHelper.GetTypeRestriction(left, right)));
}
return(BinderHelper.NoResult(_name, this.ReturnType, left, right));
}
/// <summary>
/// 比較方法を検索し、見つからなかったら例外を投げるMetaObjectを返す。
/// </summary>
private DynamicMetaObject Search(DynamicMetaObject left, DynamicMetaObject right)
{
return
(TryCalcDefferentNumberType(left, right) ??
TryImplicitCast(left, right) ??
TryUseIComparableT(left, right) ??
BinderHelper.NoResult("比較", this.ReturnType, left, right));
}