Geek Answers Handbook

Checking compilation time in a contract project?

I read that the compiler can force dbc to run at compile time. How to do it?

+3
source share
5 answers

As far as I know, SpeC # from Microsoft Research is the most powerful static DbC language yet . It uses a powerful static analysis tool called Boogie , which in turn uses a powerful probe for checking the theorem / Constraint Solver, called Z3 , to prove the fulfillment or violation of contracts during development.

If the proof of the theorem can prove that the contract will always be violated, this is a compilation error. If the probe of the theorem can prove that the contract will never be broken, then optimization: contract checks are removed from the final DLL.

As Charlie Martin points out, proving contracts is generally equivalent to solving the stop problem, and therefore impossible. Thus, there will be many cases when the theoretician can neither prove nor disprove the contract. In this case, a runtime check is issued, as in other, less powerful contract systems.

Please note that Spe # is no longer being developed. The contract mechanism was extracted to a library called Code Contracts for.NET , which will be part of .NET 4.0 / Visual Studio 2010. However, language support for contracts will not.

+5

? . , (: , , ). - . , .)

,

  foo(a);

-

  function foo(a:int) is
     assert 0 < a && a < 128
     ...
  end

, a (0..128).

+1

, , . (++):

double x;
cin >> x;
cout << sqrt(x) << endl;

, sqrt , , , . , :

double x;
cin >> x;
if (x >= 0) {
    cout << sqrt(x) << endl;
} else {
    cout << "Can't take square root of negative number" << endl;
}

, sqrt .

+1

- , . , . .

, , , , , .

, . , , S, , S.

+1
source

Some languages, such as D , have a fairly powerful compile-time integrity check and compile-time check (for D static assert(boolCond, msg);, IIRC C / C ++ can use #ifand pragmaor #error)

0
source

More articles:


All Articles