DPaste - Paste #1280 - pastebin, online compiler and collaboration tool dedicated to D Programming Language

Code

struct scope_ptr(T : Object) {
private:
	T* _ptr;

public:
	@disable
	this(typeof(null));

@disable
	this(this);

this(ref T obj, string filename = __FILE__, uint line = __LINE__) {
		if (obj is null) throw new Exception("Ptr of type " ~ T.stringof ~ " is null.", filename, line);

this._ptr = &obj;
	}

this(T* ptr, string filename = __FILE__, uint line = __LINE__) {
		if (ptr is null) throw new Exception("Ptr of type " ~ T.stringof ~ " is null.", filename, line);

this._ptr = ptr;
	}

~this() {
		destroy(*this._ptr);

*this._ptr = null;
		this._ptr  = null;
	}

bool Valid() const {
		return *this._ptr !is null;
	}

bool opCast() const {
		return this.Valid();
	}

@property
	inout(T*) Access(string filename = __FILE__, uint line = __LINE__) inout {
		if (this._ptr is null) throw new Exception("Ptr of type " ~ T.stringof ~ " is null.", filename, line);

return this._ptr;
	}

alias Access this;
}

void main() {
	import std.stdio;

class Foo {
	private:
		void print() const {
			writeln("I'm Foo.");
		}
	}

Foo f2 = new Foo();

{
		scope_ptr!(Foo) sp = f2;
	}

writeln(f2 is null); // prints true
	writeln(f2); // prints null
	f2.print(); // works fine

if (f2) {
		writeln("if #1"); // will not printed
	}

if (f2 !is null) {
		writeln("if #1"); // will not printed
	}
}

Application output:

true
null
I'm Foo.

Paste info

Author: Namespace

Views: 209

Private: no

Expires: Never

Uploaded: 12.08.12 0:22

Votes: 0

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Compiler: DMD 2.062

Pointer size: m64

Code

Application output:

Paste info

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