managable.js -- primitives for facilitating "reference counted" resources

managable.js

function managableFactory () {

	var _broken = Promise.resolve(null);

	function Managable () {

	}

	Managable.prototype.rref = function () {
		return null;
	};

	Managable.prototype.rretain = function () {
		return this;
	};

	Managable.prototype.rrelease = function () {
		return this;
	};

	Managable.prototype.rreclaimed = function () {
		return _broken;
	};

	var _unobservable = new Managable();
	var _invalid = new Helper(0|!!"unobservable");
	_invalid.retainCount = 0;

	function _noop () {}

	function Helper (unobservable) {
		var abandon;
		this.retainCount = 1;
		this.thenable = unobservable ?
			_broken : new Promise(function (resolve) { abandon = resolve; });
		this.abandon = unobservable ?
			_noop : abandon;
	}

	return function managedFactory (silent, minimal, unsafe, loud) {

		var _safe = unsafe ? null : new WeakMap();

		var Managed = unsafe && loud ? function () {
			this[unsafe] = new Helper(0|!"unobservable");
		} : unsafe ? function () {
			this[unsafe] = 1;
		} : minimal ? function Managed () {
			_safe.set(this, 1);
		} : silent ? function Managed () {
			_safe.set(this, new Helper(0|!!"unobservable"));
		} : function Managed () {
			_safe.set(this, new Helper(0|!"unobservable"));
		};

		Managed.prototype = new Managable();

		Managed.prototype.rref = unsafe && loud ? function nested () {
			return ((this[unsafe] || _invalid).retainCount > 0) ? this : null;
		} : unsafe ? function unrestricted () {
			return (0|this[unsafe] > 0) ? this : null;
		} : minimal ? function helpless () {
			var _retainCount = 0|_safe.get(this);
			return (_retainCount > 0) ? this : null;
		} : function helpful () {
			var _helper = _safe.get(this) || _invalid;
			return (_helper.retainCount > 0) ? this : null;
		};

		Managed.prototype.rretain = unsafe && loud ? function nested () {
			var _helper = this[unsafe] || _invalid;
			if (_helper.retainCount > 0) _helper.retainCount++;
			return this;
		} : unsafe ? function unrestricted () {
			var _retainCount = 0|this[unsafe];
			if (_retainCount > 0) this[unsafe] = _retainCount + 1;
			return this;
		} : minimal ? function helpless () {
			var _retainCount = 0|_safe.get(this);
			if (_retainCount > 0) _safe.set(++_retainCount);
			return this;
		} : function helpful () {
			var _helper = _safe.get(this) || _invalid;
			if (_helper.retainCount > 0) _helper.retainCount++;
			return this;
		};

		Managed.prototype.rrelease = unsafe && loud ? function nested () {
			var _helper = this[unsafe] || _invalid;
			if (_helper.retainCount > 0 && --_helper.retainCount < 1) (0, _helper.abandon)(this);
			return this;
		} : unsafe ? function unrestricted () {
			var _retainCount = 0|this[unsafe];
			if (_retainCount > 0) this[unsafe] = _retainCount - 1;
			return this;
		} : minimal ? function helpless () {
			var _retainCount = 0|_safe.get(this);
			if (_retainCount > 0) _safe.set(--_retainCount);
			return this;
		} : function helpful () {
			var _helper = _safe.get(this) || _invalid;
			if (_helper.retainCount > 0 && --_helper.retainCount < 1) (0, _helper.abandon)(this);
			return this;
		};

		Managed.prototype.rreclaimed = unsafe && loud ? function nested () {
			return (this[unsafe] || _invalid).thenable;
		} : unsafe ? function unrestricted () {
			return _broken;
		} : minimal ? function helpless () {
			return _broken;
		} : function helpful () {
			var _helper = _safe.get(this) || _invalid;
			return _helper.thenable;
		};

		return Managed;

	};

}