Re: References and constant pointers

Hi

I would translate 'val x = ref 0'; as 'int x = 0', as 'x' is simply a
'int * const' in C by itself. This simply reflects that in ML stateful
computation is explicitly defined, whereas in C is implicit (everything
is carrying state)... and, besides, C programs derived from ML don't
have to be that complicated ;-)

cheers
Carlos Aya
p.s. let recommend you this http://www.info.ucl.ac.be/~pvr/book.html
for further reading about stateless/stateful programming paradigms.

cane wrote:
Hi, I'm trying to better understand the concept of reference in SML.
For what I've been able to grasp till now, and trying to draw an
analogy, a reference variable is much like a constant pointer in C, e.g.:

this SML snippet:

val x = ref 0;

Could be translated in C to something like:

int val = 0;
int* const x = &val;

Basically, you can modify the value of the pointed variable, but you
can't modify which variable the pointer points to.

So, standing the definitions above, you can do (SML): x := 1; as you can
do (C): *x = 1; but you cannot do (SML): val x = ref 1; (new binding for
the same identifier) as you cannot do (C): x = &val2; is that correct?

Thanks, bye.



.

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