Null references (oh no, not again!)

[bearophile]

Walter Bright:
> Global switches are not appropriate for anything other than debugging, 
> however, because some libraries may depend on overflow arithmetic.

Right. If a library needs wrap arounds in numbers to work correctly, it has to contain a command to locally switch off overflow checks; such annotations override the global behavior of the compiler. This is how things work in Pascal-like languages. And it also shows why you need both global and local ways to switch them on and off.

Bye,
bearophile