function ffalse() {
	return false;
}

function ftrue() {
	return true;
}

function setControlsVisible(visible) {
	for (var i = 1; i < arguments.length; ++i) {
		var control = document.getElementById(arguments[i]);
		if (control != undefined && control != null) {
			control.style.visibility = visible ? "visible" : "hidden";
		}
	}
}

function addToCSVSet(setstring, value) {
	var values = setstring != "" ? setstring.split(",") : new Array();

	var exists = false;
	for (var i = 0; i < values.length; ++i) {
		if (values[i] == "" + value) {
			exists = true;
			break;
		}
	}

	if (!exists) {
		values.push(value);
	}

	return values.join(",");
}

function removeFromCSVSet(setstring, value) {
	var values = setstring != "" ? setstring.split(",") : new Array();

	var newValues = new Array();
	for (var i = 0; i < values.length; ++i) {
		if (values[i] != "" + value) {
			newValues.push(values[i]);
		}
	}

	return newValues.join(",");
}