Fixing C's Biggest Mistake

[Dukc]

On Tuesday, 27 December 2022 at 09:41:59 UTC, Max Samukha wrote:
> If T.init is supposed to be a valid value, then the constructor 
> receives an already initialized object (not some "branded" 
> abberant), so the constructor actually plays the role of 
> assignment.
>
> If T.init is supposed to be an invalid value useful for 
> debugging, then variables initialized to that value... are not 
> initialized.

The `.init` value is supposed to be both. A null pointer is a 
good example. It is valid in the sense it's behaviour is 
reliable. Dereferencing it always crashes the program, as opposed 
to undefined behaviour. Also it will reliably say yes when 
compared to another null pointer.

But it is also an useful value for debugging, because accidently 
using it immediately crashes and produces a core dump, making it 
obvious we had a null where there shouldn't be one. Also when 
debugging, pointer to address `0x0000_0000_0000_0000` is clearly 
uninitialised, while a pointer to whatever happens might look 
like it's pointing to something valid.