[RFC] type safe trees

[Richard Kenner]

    Can we all agree to just flat kill that stupid nonsense?  It's a causal
    (not "casual") form of the slippy-slope argument, which is typically wrong.
    It implies that nobody would /notice/ if other facets of the language
    suddenly appeared in the compiler sources.  It implies that we can't use
    any part of C++ without using all of it, which any decent C++ programmer
    should find a little insulting, as the language was expressly designed to
    support using only parts of it.

That's not where I see the "slippery slope" argument.  I don't see the
concern as one of sloppy programmers not noticing they were violating the
subset, but that once the big step was taken to use C++ in the first place,
we could *consciously* increase the size of the subset from time to time and
soon enough it wouldn't be much of subset anymore.

So I *do* think that we need to be extraordinarily careful before we
take the first step here because it's likely we'll have much less trouble
taking the subsequent ones.