On 5/18/2013 5:23 PM, deadalnix wrote:
On Sunday, 19 May 2013 at 00:14:26 UTC, Walter Bright wrote:
this() { assert(0); }
makes for a runtime check, not a compile time one. Compile time checks are
more efficient in both programmer time and run time.
Note that C++11 8.4.3 has @disable as well, in the form:
S() = delete;
D has @disable. If default constructor are allowed, default constructor can be
disabled, as any other declared symbol.
I understand that. But the rationale you gave for having a default constructor
was to be able to disable default construction.
With NotNull, the runtime check only happens upon assignment and
initialization from a pointer type. Dereferencing, copying, etc., of NotNull
entails zero runtime overhead and no checks.
People go for the shortest path. You end up having nullable everywhere.
Experience have been a countless amount of time in bazillion programming
languages. But it is probably too late to fix this in D anyway.
I know that some languages have a special syntax for non-null pointers. I
disliked this solution for D because non-nullable pointers are just one instance
of creating a type with a limited set of values. Why not go for a general
solution? Why not create a mechanism where a type can be defined that can only
consist of prime numbers, for example? Why not ranged integer types?
