On 05/08/2014 07:03 AM, Marko Rauhamaa wrote:
Ethan Furman <et...@stoneleaf.us>:
On 05/08/2014 05:41 AM, Roy Smith wrote:
For those people, talking about variables as a container to hold a
value is the right level of abstraction.
Teaching someone that Python variables are containers is a massive fail.
But that's what they are.
No, it's not.
We are really debating on the suitability of a metaphor.
Exactly. And the "a variable is a box that holds the value" is a great metaphor for languages that assign a name to a
fixed location -- languages such as Pascal, Basic, FoxPro, and C. In these languages when you say `a = b` you now have
*two* copies of the data (at least for the most part); in Python (and similar languages) you have two *names* for one
copy of the data.
Or maybe we can think of Python's data model as a city with structures
of different sizes and shapes. A variable is a container that holds the
address of a structure...
If that helps as a stepping stone to a true model, fine; but if that's the final destination of your understanding then
you don't truly understand Python's data model.
--
~Ethan~
--
https://mail.python.org/mailman/listinfo/python-list
