Documentation for method
ASSIGN-KEY assembled from the following types:
multi method ASSIGN-KEY (::?CLASS: , )
Expected to set the element associated with
$key to the value
$new. Implementing this is entirely optional; if you don't,
self.AT-KEY($key) = $new is used instead, and if you do, you should make sure it has the same effect.
This is meant as an opt-in performance optimization, so that simple assignments
%age<Claire> = 29 can operate without having to call
AT-KEY (which would have to create and return a potentially expensive container object).
Note that implementing
ASSIGN-KEY does not relieve you from making
rw method though, because less trivial assignments/modifications such as
%age<Claire>++ will still use