Forum Post: RE: SKILL++: Changing += to apply for user-defined classes

Hi Lior, I'm not entirely sure what you mean by "apply the =+ inits' context". When you use the += operator, it's translated from: a+=x to: setf(a a+x) You can define the setf updater function using defsetf() - this was partly covered in the Advanced SKILL training (that you were on). It's also possible to override what the + operator does in a lexical scope by defining a local function plus with different behaviour. I don't really want to dive into giving an example of doing this without better understanding what you're hoping to achieve, as otherwise I may just add rather than subtract confusion! By the way, there is no =+ operator in SKILL - the parser will not recognise it - only +=. Regards, Andrew.