Hello, VladD2, you wrote: VD> With you it is almost impossible to argue. You are a priori right. After all you define that a sentence wrong, and such trifles as the argumentation of you do not trouble. , it is accepted Wrong - not absolutely correct word. I can replace on "as a result will not work without breakage of compatibility with an existing.net-code" then like all it is true. VD> I, here, with you and do not want to argue. I already use more than 10 years language where "wrong" sentences perfectly work in practice and preserve against a row of errors. Here on a fig to me to you something to prove? Continue to consider as correct only that the MSEC and write next WHF. Well so you also do not have heavy heritage in the form of a heap , necessities of design under 95 % community and needs to save compatibility with the code written 17 years ago, truly? The people in.Net Core already tried to go such way. Two years it as though worked, and then suddenly came from big clients. As a result as early as two years of a work involving all hands and at us again almost compatible with.full net FW. Not as dispute, it is really interesting: and how in language simultaneously to implement sql-style operators for nullables and thus not to break dictionaries/sorted set? Or we do so that implementations of operators and standard equatable/comparable-interfaces did not coincide, or we continue to attack a rake.