He thought that the change of del he proposed will give him that behavior, but this is not true.
Unless I'm forgetting part of the conversation, that's not true. Note that the numpy patch is merged. Today, you get the optimization with `z = a + b + c + d`. What you don't get is the same optimization if you use: ``` ab = a + b abc = ab + c z = abc + d ``` The language feature I propose is to allow you to _keep_ the optimization that was present in `z = a + b + c + d`, but write it as ``` ab = a + b abc = (del ab) + c z = (del abc) + d ```