Broken contract programing

[iackhtak via Digitalmars-d]

On Wednesday, 13 May 2015 at 12:05:48 UTC, Timon Gehr wrote:
> On 05/13/2015 12:51 PM, iackhtak wrote:
>> There was discussion about broken contract programing. One 
>> broken
>> thing was "in" contract within inheritance. If you add 
>> different
>> "in"-contract in overridden parent and derived function only 
>> one
>> will be checked.
>
> No, this is incorrect. Only one needs to pass and if one does 
> not, the other is checked as well.
>
> class C{
>     int foo()in{}out(r){assert(r<=10);}body{
>         return 3;
>     }
> }
> class D: C{
>     override int 
> foo()in{assert(false);}out(r){assert(r>=10);}body{
>         return 10;
>     }
> }
>
> void main(){
>     D d=new D();
>     d.foo();
> }
>
> What is the problem?
>
> The problem you may have read about is that if no contract is 
> specified for an overriding function, the parent contract is 
> automatically loosened completely:
>
> class C{
>     void foo()in{assert(false);}body{}
> }
> class D: C{
>     override void foo(){}
> }
>
> void main(){
>     D d=new D();
>     d.foo(); // ok
> }

So I misunderstood this feature:( But the topic thing still a 
solution.