On Thu, Apr 21, 2011 at 12:13 PM, Stewart, Robert <Robert.Stewart@sig.com>wrote:
Jeffrey Lee Hellrung, Jr. wrote:
On Thu, Apr 21, 2011 at 10:29 AM, Stewart, Robert <Robert.Stewart@sig.com>wrote:
Joachim Faulhaber wrote:
FWIW, I agree with Joachim on this point. Since they both deal with builtin C++ operators (something in common), *it would be nice* if the part of the name referring to the operator (the common part) were the same (or a slightly varied). The semantic difference between the functor and the trait should, IMO, primarily be conveyed by the prefix or suffix or the particular variation on the "primary" operator name.
OK. Is "multiplication" a slight enough variation of "multiplies?"
[...] Yes... Did you try the thought experiment I suggested in my last post?
To some extent, as I already have a number of these traits lying around. Looks like, at the time I created these, I preferred the "is_xxxable" form for those traits (is_left_shiftable, is_pre_incrementable, etc.). I guess I was naming the trait after the operation rather than the operator. I think some for some operators, though, that formula is a bit awkward, e.g., with "+=". I would think to call that "has_plus_equal" or "has_operator_plus_equal" or "can_call_plus_equal" depending on what the understood prefix was. It seems we're going with the "name after the operator" route, here, which I have no problem with; it's easier to apply that formula universally to all operators, I think, and that's probably what Frederic discovered as well. Then a question is what to call each operator. I wouldn't initially think to call "+=" the "addition assignment" operator, but that's just me.
Also, while we're on the topic of what *I* prefer: I still
prefer "has_xxx". To me, it has an implicit association (to me, anyway) to the names of trait predicates; it has simplicity and brevity; and it has existing use in Boost.TypeTraits.
What about all of the "is_" prefixed traits
Those, too!
and other names in Boost.TypeTraits with prefixes like "add_" and "remove_,"
Those aren't predicates...
and those without a prefix?
Such as...?
There's clear precedent for different prefixes for different purposes within the library. Remember that "has_" implies ownership or inherent characteristic which doesn't apply to a namespace scope operator.
Well, I don't think it's confusing to say that "A has a plus operator" is equivalent to "A + A is well-formed". Like I said, I understand that arguments against "has_xxx", but it's still more natural to me than "can_call_xxx". - Jeff