const?? When and why? This is ugly!

[Christopher Wright]

bearophile wrote:
> Lutger:
>> If you have a dynamic language you have a different way of programming. In D 
>> when I make a typo, the compiler catches it. When I do the same in Ruby, I 
>> have a unit test that spits out a method missing exception with a trace. 
>> Suppose D doesn't catch my typo and then my application crashes at runtime 
>> without such a trace, that will be a nightmare. 
> 
> This is a complex and long debated topic.
> In my D programs I put almost as many unittests as I put in Python programs, because experience shows me the type system of D doesn't catch that many bugs. The result seems strong enough D programs.
> While I debug I use the 'Phobos hack' to add something like those traces to D (I don't understand why such feature isn't built-in yet, it's essential when I debug D programs).

Agreed on testing, and agreed on stack traces.

However, how do you test the unit test system?