RAII is not precluded by explicitness, you could require all values that require cleanup to be syntactically marked in some way and it would still be RAII. defer also cannot handle resources whose lifetimes do not correspond to nested scopes (eg. the elements of an ArrayList) like RAII or a GC can.
I think this one is TBD.
> defer also cannot handle resources whose lifetimes do not correspond to nested scopes (eg. the elements of an ArrayList) like RAII or a GC can.
Yep, defer won't work if there is no known lifetime scope, but I think this one is actually a good tradeoff to make in a low-level language. Don't get me wrong -- I love tracing GCs and think that they're the right choice for the vast majority of application software, plus there have been great strides made in GC capabilities in the past few years, but in the domains where low-level languages are appropriate there is a different set of constraints. Low-level programming is not like high-level programming, and IMO it's wrong to even try to make them look alike.
It can, it's just more explicit about it. In a language with destructors, you'd do RAII here by having a list destructor that cleans up each element in turn. In a language with defer, the same destructor becomes a regular function that you'd invoke in the deferred expression.
