so wrote:
Examine the API of a function in a library. It says it doesn't modify
anything reachable through its arguments, but is that true? How would
you know? And how would you know if the API doc doesn't say?
You are right, but try to look at this from another angle (probably i am
not making any sense here). Should "D const" be perceived this way?
When i say "const A", it broadly means don't assign to this.
That's "head const", which is what C++ has. The const system in C++ does not
work. If you view const strictly as a storage class, that fails as soon as you
introduce pointers.
You'd fall back to const by convention, and that is not reliable and
does not scale. You have to manually go through an entire hierarchy of
function calls to figure out if one might change a member of the data
structure, and then after a few maintenance cycles, you have to do
that all over again.
I have no idea how to solve this for documentation and such but the
second you compile the source, everything will be clear as day.
As I wrote in another reply to you, there are many cases where the compiler
cannot determine this.
