Re: scheme set list function

[Aaron Hill]

On 2019-04-08 5:31 am, Andrew Bernard wrote:
> Hi All,
>
> Here's a very well written post on pointers in Scheme (it doesn't have
> them, full stop). Wonderful language that it is, you can create 
> something
> similar for yourself.

We do not have access to pointers in the Scheme language, as it is 
intended to be abstract from such a lower-level detail.  But that 
doesn't mean there are no pointers behind the scenes.  An 
interpreter/compiler is free to implement the language however it sees 
fit.  If you were writing in C, then you are almost certainly going to 
be leveraging pointers.

The point here is that some form of indirection must be occurring, since 
it is possible to pass in a list to a procedure and have that list be 
modified.  Yes, we are not modifying the variable in the caller's scope; 
but we are modifying what it *refers* to.  Hence, why I had considered 
it pass-by-reference.

Obviously, I am in error with my terminology.


-- Aaron Hill