Differences With TDPL

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The following is a list of differences between D2 and The D Programming Language book by Andrei Alexandrescu.

These need to be verified. This list was simply gathered from a post by Jonathan M. Davis on the NG to get this page started.

New Features

Weak vs Strong Purity


New Lambda Syntax


New Alias Syntax, Alias & Enum Templates

http://dlang.org/declaration.html#AliasDeclaration https://github.com/dlang/DIPs/blob/master/DIPs/archive/DIP42.md

Attribute Inference for Templates and Function Literals


IFTI now uses the tail-const type of arrays and pointers

For example code, see: http://forum.dlang.org/post/mfjmysleuwfohoxcslpf@forum.dlang.org

DIP25 - return ref


DIP60 - @nogc function attribute


DIP1000 - scoped pointers


DIP1010 - static foreach


Unimplemented / Incomplete Features

Multiple alias this

You can only have one subtyping member currently.

Synchronized Classes

For the most part, synchronized for classes currently acts like it does in Java with synchronized being on functions. The compiler does complain about having public members if a class is marked as synchronized, but none of the stuff like automatically stripping off the outer layer of shared in member functions is implemented, and the compiler allows you to put synchronized on individual functions without putting it on the class, which TDPL explicitly says is disallowed.


Not all of shared's guarantees are implemented yet. In particular, shared has no implicit memory barriers, and it's not clear that it ever will (they're not cheap). shared is usable as-is via atomic operations (as described in TDPL) or locking mutexes (be it explicit or via synchronized), but without synchronized classes, using shared typically requires temporarily, explicitly casting shared away after protecting the object with a lock so that it can be operated on as if it were thread-local while protected by the lock.


Overriding private methods

According to TDPL, you can override private, but right now only public and protected functions are virtual. I'm not sure that it's 100% clear whether the compiler will be changed to match or whether TDPL is going to have to be changed. You can look at http://d.puremagic.com/issues/show_bug.cgi?id=4542 for details.