Reddit: SafeD - The Safe Subset of D

[Dejan Lekic]

I wish D uses the concept of UNSAFE modules similar (or the same) as in 
the excellent Modula-3 language (which influenced all modern OO 
languages, IMHO).
Modula-3 has a keyword "UNSAFE" which is used in a module or interface 
declaration to indicate that it is _unsafe_. In other words it informs 
us that the module/interface uses unsafe features of the language. If 
module or interface is not labeled "unsafe" (default behavior), it is 
assumed to be safe.
This simple concept is amazing, as is the fact that Modula-3 (as a 
language) had this (plus numerous other modern features) two decades ago.

Kind regards

PS. I am not advocating Modula-3 here. I do C++ (16 years), D, Java and 
PHP programming, mostly.