Re: [boost] Re: Invariants Library

From: Darren Cook (darren_at_[hidden])
Date: 2004-01-02 01:41:23

>> Has there been any discussion regarding an invariants library 
>> (advanced assert), or is there one already implemented in boost?

There is smart-assert by John Torjo (http://www.torjo.com/smart_assert.zip) 
which might end up being submitted for Boost review. I've been using it on 
some projects for a few months now and find it useful. If only there was a 
way to generate a stack trace I might never need to use a debugger again :-).

> The compiler I'm using, Digital Mars version 8.38 already supports 
> invariant, pre- and post-conditions. See...
> http://www.digitalmars.com/ctg/designbycontract.html

Are there any other compilers planning to use these?

Is it working under the hood by generating assert commands, or doing 
compile-time checking? E.g. would the square_root() example (included below) 
create a compile-time error for this?
   square_root(-1);

If so, what about this:
   void myfunc(long n){
    square_root(n);
    }

   myfunc(-1);

Darren

*:
        long square_root(long x)
            __in
            {
                assert(x > 0);
            }
            __out (result)
            {
                assert((result * result) == x);
            }
            __body
            {
                return sqrt(x);
            }