This is the slide in question.
aliceis not the name of the object. It is the variable that holds an object. Invoking the name of a variable references the contents.- The dot operator is used to reference not to call.
alice.movedoes not callmove, it references it. The()make it a call. - The empty set of parentheses is the call not the
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I like a tight vocabulary in the classroom. Too much? Sorry.
I am very careful about “call” and “reference” as I talk. An experienced programmer can sort out the difference between call and reference but not a beginner.
I also like to set the students up to understand . in both methods and attributes by talking about it as the access operator. Google says it is really the “member access operator.” We will also use it to find things in imported packages as well. It could be explained as being like commas in a post office address. While we use an address like 1234 Main Street, Livonia, Michigan at the post office in Python would do Michigan.Livonia.Main Street.1234
It also explains why alice.move does not throw an error. It is perfectly legal to reference a method or function but not call it, which sets them up to understand functions as first class objects.