Invariants for methods

[bearophile]

Jens Mueller:

> I don't like the "old" approach.

Why?
(It's the canonical way to solve the problem you have had. It is present in Eiffel and C# and probably something similar is present in the DbC for Java. But surely other solutions are possible.)


> Don't get your point here. You neither like the ghost fields (old) nor
> the debug {} approach as Andrei suggested?

I have written that answer of mine before reading Andrei answer.


> I mean after all the problem
> is not that important that one should bother too much.

The problem is important enough. In DbC it's very useful to have a safe&notbugprone way to test if a method has changed the precedent state correctly.

Bye,
bearophile