0 a long, narrow hole, especially one for putting coins into or for fitting a separate piece into -- 狭缝；（尤指）投币口，狭槽
1 an amount of time that is officially allowed for a single event in a planned order of activities or events -- （为某活动安排的）时段
2 to put something into a slot or fit together using slots -- 被（能）放于狭槽中
Even for much smaller classes, this is impractical because, in general, overloading dispatches on types only and several slots can have the same type.
Each class defines a set of slots that implement the configuration of the instances.
In this case, messages can be destroyed by superimposition in overlapping slots.
An example is the use of so-called 'templates', string patterns that contain empty slots where other strings must be filled in.
Each class declaring virtual slots contains a vector of virtual slots accessors.
The arcs interconnect the concepts and represent lexical-semantic relations ; they are implemented by means of frame slots containing pointers to other concepts.
We are presenting a function that prints the value of the slots of the point and point-3d instances.
In the following class definition, the width and height slots are virtual.
