I find the standard to be very clear and concise regarding lvalue/xvalue/prvalue [2011 3.10.1]. I wonder if teaching from the standard is a better way of appro

I find the standard to be very clear and concise regarding lvalue/xvalue/prvalue [2011 3.10.1]. I wonder if teaching from the standard is a better way of approaching this, ie: start with the standard, then just explain what it means.