On Saturday, 16 March 2013 at 14:40:58 UTC, D-ratiseur wrote:
new is overriden in TUObject because the purpose of the library is to bypass the garbage collector and to bypass the GC you have to override new and delete.(at least according to the manual: articles,mem managment).

The documentation on this is old and misleading.

Overloading of new and delete is deprecated (the delete operator in its entirety is deprecated).

Having them overloadable was not a very good idea. The current approach is to have "new" always mean GC memory, which is why there is no need for delete. This way, code that uses 'new' won't break horribly or leak depending on the type involved, important for generic code. Code that doesn't use the GC has to be designed for it; you can't just remove the GC under everyone's noses and expect things to work.

For different kinds of memory, you should simply use a different allocator. For example, here's a rough approximation of a pair of functions using malloc/free for class allocation:

T alloc(T)() if(is(T == class))
{
        enum size = __traits(classInstanceSize, T);
        auto p = enforceEx!OutOfMemoryError(malloc(size));
        return emplace!T(p[0 .. size]);
}

void dealloc(T)(ref T obj) if(is(T == class))
{
    free(cast(void*)obj);
    obj = null;
}

It can easily be overloaded to support all types.

In the future, Phobos will have a custom memory allocator library, which modules like std.container will use, though to which extent is not clear (for example, will it also use the custom allocator for exception objects?). Nevertheless it will probably be a good base for other libraries to easily support non-GC allocators.

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