A proper language comparison...

[bearophile]

Peter Alexander:

> - What's safe and unsafe is very subjective.

There are large bodies of people that count bugs in code, and 
correlate them with coding practices. They have created language 
subsets like C for automotive industry, C++ for aviation, code 
for space missions, Ada language and its successive refinements 
like Ada2012, SPARK subset of Ada. There are lot of people trying 
sideways solutions, at Microsoft (Spec#, Liquid typing, etc), 
dependent typing (ATS language), and so on and on, even Haskell 
variants. Lot of this stuff is not based on statistical data, but 
there is also some hard data that has shaped some of those very 
strict coding guidelines. There are several serious studies in 
the field of coding safety. Dismissing all that decades old work 
with a 'very subjective' is unjust.

As usual D code safety is mostly correlated to the coding style 
you are using, how you write your unittests and code contracts, 
how much good are your code reviews, how much careful your 
programmers are, etc. But the language design is also a factor. 
To me D safety looks about intermediate between C and Ada-SPARK. 
D code normally has undetected integral overflows, it doesn't 
help a lot against null pointers (Nullable is not so good yet), 
there is no significant stack overflow protection, no 
variable-sized stack-allocated arrays that help a bit created 
bounded collections, the management of reference escaping is 
planned but not yet implemented (scope), and so on. Overall to me 
D coding seems significantly safer than C coding, and perhaps 
it's a little safer than C++11 coding too. I know no studies 
about the safety of D code compared to C++11 code or Ada2012 
code, or compared to other languages.

Bye,
bearophile