I don't know whether this is theoretical, philosophical, or in any way relevant to what we are *supposed* to be discussing here - but to break what I consider to be an uncomfortable silence I thought I'd throw it out into the excess bandwidth, nonetheless:
I do in fact use properties in various places in my code, and but not generally in ways I find compelling or truly functional - maybe some nuance of "interface" that I could easily live without. I seem , however, to have come across my first more compelling use case. I went with the creation of a mutable complex number type, which I then inherit from and use down the line. But when I send instances of classes derived from this custom type to use as elements of a Numeric Userarray, there is no way that I have found to be able to tell Numeric that if it treats these instances as if they were built-in complex numbers, things should work out OK. Numeric seems to insist on creating arrays of Python instances, and then insists it does not know how to do math with Python instances. So properties come in handy essentially to do casting - from the custom Complex type to the built-in complex type on the way into the UserArray, and in reverse on the way out - i.e, set and get. This only additionally meant customizing the Numeric UserArray to derive from object (it doesn't come that way) , before I go further with it, so that properties "take". I am sure I am taking at least a bit of a performance hit by going this route. Does anyone see something simple I may be missing here to get to where I am trying to get, without the hit? Art _______________________________________________ Edu-sig mailing list Edu-sig@python.org http://mail.python.org/mailman/listinfo/edu-sig
