Is D still alive?

[Daniel Gibson]

Am 28.01.2011 13:30, schrieb spir:
> On 01/28/2011 12:36 PM, bearophile wrote:
> 
>> I think the problem here is that you are not using your D tools well enough yet:
>> - Preconditions allow you to save some tests in your unittests, because you
>> have less need to test many input boundary conditions.
>> - Postconditions are useful to save some code to test the correctness of the
>> results inside your unittests. You still need to put many tricky but correct
>> input conditions inside your unittests, but then the postcondition will test
>> that the outputs are inside the class of the correct outputs, and you will
>> need less unittest code to test that the results are exactly the expected ones
>> in some important situations.
> 
> Very intersting points, thank you.
> 
>> - The missing "old" feature once somehow implemented allows to remove some
>> other unittests, because you don't need a unittest any more to test the output
>> is generally correct given a certain class of input.
> 
> What is this "old" feature?

if you've got a function fun(int x){ ... ; x++; ... }
then you can use old.x (or something like that) in the dbc block at the end to
access the original value of x.
like assert(x == old.x+1) or something like that.
after hearing about dbc in university I thought that having old was fundamental
for dbc.. but D doesn't support it.

Cheers,
- Daniel