Why is &array[0] @safer than array.ptr?

[David Nadlinger via Digitalmars-d-learn]

On Wednesday, 25 January 2017 at 22:59:55 UTC, Jonathan M Davis 
wrote:
> Yes, but my point is that you're normally only going to use 
> .ptr to pass something to a C function, and even if you're 
> doing more with it in D, odds are, you're going to be doing 
> pointer arithmetic.

Wrong again. If this were the case, we wouldn't have needed to 
make it a deprecation at all, since all uses would have been 
mistakes. A non-negligible amount of real-world D code actually 
uses single-object pointers. Look up the change history if you 
are interested – and indeed, making sure one understands the 
topic sufficiently well to meaningfully contribute before typing 
out a wall-length sermon would collectively save us a good chunk 
of time.

> And when you combine it with marking C function @trusted, this 
> is actually pretty bad.

Ex falso quodlibet – once you have a piece of code mistakenly 
marked @trusted, all guarantees are out of the window even 
without suspicious-looking client code. @safe-ty is about 
mechanically verifiable code, not faith-based programming.

  — David