Aaah ... I *now* see the connection. Thanks for the clarification.
Interesting that you mentioned 'bool'. I hadn't overloaded it so, as you pointed out, any boolean evaluations were based on what the overloaded
returned. I was aware that was happening - and it was pretty much doing what I wanted (namely, returning true unless the string was "0"). It then occurred to me (only a couple of days ago) that nans and -0 would also return true - since the strings "@NaN@" and "-0" return true. That's not what I wanted, so I've now explicitly overloaded
to behave as I want.