"Alex Chovanec" <achovane@engin.umich.edu> wrote in message news:cganiq$q27$1@sea.gmane.org...
"Jonathan Turkanis" <technews@kangaroologic.com> wrote in message news:cgal34$l63$1@sea.gmane.org...
Currently there is detail::is_incrementable, which works well if
you
only need to distinguish between iterators and very different types. For instance, I would guess that very few if any containers are incrementable (I'd be happy to be proved wrong here), so that if you want define a function which behaves differently for container and iterators you can use is_incrementable.
In this case, I need to know whether or not type T is dereferenceable
I've attached a naively modified version of David Abraham's is_incrementable as a first attempt at is_dereferenceable. There may be all sorts of subtle issues I haven't though of.
(and more generally, whether or not it's an iterator).
I have a small template metaprogram which determines how an instance of type T should be
Why? When you write a template, you always have some idea of the range of types for which the template should be instantiated. It's rarely instantiable for all types. Given this, all you need is a way to separate iterators from the other candidate template arguments. treated. If
it's an iterator, I want to dereference it. Otherwise, I don't.
Don't forget pointers. Also these operators can also be defined as non-member functions.
Pointers are fairly easy to handle.
True.
You bring up an important point about operators defined as non-member functions. My current implementation doesn't handle this case, but I may yet be able to fix that. :-)
Try the attachment.
Thanks for the feedback,
Alex
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