Terminology: "reference" versus "pointer"

Rustom Mody rustompmody at gmail.com
Sat Sep 12 20:21:18 CEST 2015


On Saturday, September 12, 2015 at 11:26:18 PM UTC+5:30, Akira Li wrote:
> Rustom Mody  writes:
> 
> > On Saturday, September 12, 2015 at 8:11:49 PM UTC+5:30, Laura Creighton wrote:
> >> In a message of Sat, 12 Sep 2015 05:46:35 -0700, Rustom Mody writes:
> >> >How about lay-English ontology in which "point to" and "refer to" are fairly
> >> >synonymous?
> >> 
> >> This I have found is important in teaching, which is why I favour 'bind'
> >> and 'binding' -- rather than pointer, pointer, refer to, referring.
> >
> > Well we can play humpty dumpty and make any word mean whatever we like.
> > However if you are a teacher you will recognize a need for pictures.
> > And (as far as I can tell) "Random832" finds a need for the box-n-arrow
> > diagrams of classic data-structure books
> 
> Speaking of pictures and names in Python
> http://python.net/~goodger/projects/pycon/2007/idiomatic/handout.html#other-languages-have-variables

Yeah cute
[I think I will even use these in my classes]
However they dont address the issue that I think random832 is referring to.
viz. I have two variables (or names!) say a and b which look the same
>>> a
[[1,2],[1,2]]
>>> b
[[1,2],[1,2]]
And yet doing
>>> a[0][0] = "Oops!"
gives a data structure one "Oops!"
whereas doing it to b mysteriously gives 2

Best I can see you can only explain this 
seemingly-similar-but-structurally-different
with box-n-arrow diagrams.
Or some moral equivalent.

And some people see no advantage to playing semantics and proclaiming
"The arrows in C look similar to the arrows in python but they are not the same"


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