DMD can implicitly convert class pointer to the bool. Is it bug or terrible feature?

[ilya-stromberg]

Code examle:

import std.stdio;

class Foo
{
}

void main()
{
	Foo f;
	
	if(f)
	{
		writeln("f is true");
	}
	else
	{
		writeln("f is false");
	}
	
	f = new Foo();
	
	if(f)
	{
		writeln("f is true");
	}
	else
	{
		writeln("f is false");
	}
}

Programm output:

f is false
f is true


So, pointer implicitly converts to false if pointer is null and 
to true if pointer is not null. Is it bug or terrible feature? 
Note that we have `f is null` syntax for these cases.