I point isn't that it is impossible in theory. It is just that, in practice, we do not have a good track record of locking down pre existing languages. As much

I point isn't that it is impossible in theory. It is just that, in practice, we do not have a good track record of locking down pre existing languages. As much as Haskell is one of the more idealogically pure languages, its ecosystem is still written under the general assumption that its programmers are not malicious geniuses.