Vicente Botet wrote
Le 24/04/12 14:31, lcaminiti a écrit :
Hello all,
Boost.Contract allows to specify "assertion requirements":
/assertion-condition/, requires /assertion-requirement/
If the requirement is not met then the assertion condition is neither compiled nor checked at run-time.
Question: Shall the assertion-requirement be a nullary boolean meta-function or just a static boolean value?
For example:
CONTRACT_FUNCTION( template( typename T ) requires( boost::LessThanComparable<T> ) (T const&) (min) ( (T const&) x, (T const&) y ) postcondition( auto result = return, x< y ? result == x : result == y, requires boost::has_equal_to<T>::value // static boolean ) ) { return x< y ? x : y; // OK: T is less than comparable `<`. }
For now, the assertion requirement is a static boolean value so it can be more easily manipulated (using !,&&, ||, etc instead of mpl::not, mpl::and, mpl::or, etc). However, is there any strong reason for marking the assertion requirement a nullary boolean meta-function instead like the following code?
x< y ? result == x : result == y, requires boost::has_equal_to<T> // meta-function
Hi,
I don't know if following the the _c suffix rule in Boost could help.
x< y ? result == x : result == y, requires boost::has_equal_to<T> // meta-function
and
x< y ? result == x : result == y, requires*_c* boost::has_equal_to<T>::value // value
Yes, that is possible and a reasonable suggestion but I fear it will be confusing for the user. There are already a lot of syntactic elements users need to familiarize themselves in using Boost.Contract so I'd rather pick one syntax (meta-function or not) and offer just that. Users can make meta-functions from static values and vice versa if they need to. Thanks. --Lorenzo -- View this message in context: http://boost.2283326.n4.nabble.com/boost-contract-assertion-requirements-as-... Sent from the Boost - Dev mailing list archive at Nabble.com.