The syntax sugar you are looking for "mutating" the immutable stricts is basically what Accessors.jl does. I don't really see a reason to bring it into Base Ju

The syntax sugar you are looking for "mutating" the immutable stricts is basically what Accessors.jl does. I don't really see a reason to bring it into Base Julia if it doesn't need special things to work. The compiler can and will optimize out the stack allocation