You can overload operator true and false i looked at examples and found this http://msdn.microsoft.com/en-us/library/aa691312%28v=vs.71%29.aspx
I completely dont und
The defining property of a short circuiting operator is that it doesn't need to evaluate the right side if the left side already determines the result. For or if the left side is true the result will be true in any case and it's unnecessary to evaluate the right side. For and it's the same except that if the left side is false the result will be false.
You need to overload both | and true to get ||. And & and false to get &&.
a||b corresponds to something like op_true(a)?a:(a|b). So if the true operator returns true it does not need to evaluate the expression of b.
a&&b corresponds to something like op_false(a)?a:(a&b). So if the false operator returns true it does not need to evaluate the expression of b.
Overloading the short circuiting operators is useful when creating a custom boolean type, such as nullable bools(See DBBool)