NULL: The worst mistake of computer science? (2015)
&gt; it means that C-strings cannot be used for ASCII or extended ASCII. Instead, they can only be used for the unusual ASCIIZ.<p>This is a very pedantic quibble, and I&#x27;m not even sure it&#x27;s correct. ASCII has NUL as well, and ASCIIZ isn&#x27;t a character set AFAIK.<p>&gt; C++    NULL    boost::optional, from Boost.Optional<p>First of all, nullptr, second, std::optional.<p>&gt; Objective C    nil, Nil, NULL, NSNull    Maybe, from SVMaybe<p>Nil is not a thing in Objective-C, to my knowledge.<p>&gt; Swift        Optional<p>You&#x27;re looking for nil. So it should be four stars?<p>&gt; Swift’s UnsafePointer must be used with unsafeUnwrap or !<p>You&#x27;re confusing Optional and UnsafePointer.