Top 5

[Aarti_pl]

Andrei Alexandrescu pisze:
> Ok, per Aarti's suggestion: without speaking officially for Walter, let 
> me ask this - what do you think are the top issues you'd like to see 
> fixed in D?
> 
> Andrei

My current top 5 (+ extensions :-) ):

1. Tango/Phobos merge
	
	minimal: merge runtime - high priority

	good   : minimal + compatibility in low level modules e.g. IO,
		 variant, core types

	perfect: full merge of libraries

2. Working process of error handling / better communication with community
	
	minimal: bugs blocking most important libraries in D and
		 long standing bugs should be solved first, before
		 other tasks.

	good   : A bit more discussion when there is different point of
		 view from Walter, and from bug/enhancement reporter. I
		 saw (and unfortunately also experienced it) few times
		 that bug was changing few times status from open ->
		 invalid -> reopen -> wontfix -> reopen. That's really
		 discouraging for reporters: filling good report is
		 really time consuming, so shouldn't be dismissed
		 without good understanding of problem.

	perfect: Walter drops his backend and work together with LDC
		 (previously LLVMDC) team on modernized compiler.
		 Probably one reason of current situation is lack of
		 manpower. Completely open frontend and open process
		 should solve also this problem. If Walter would decide
		 to go this way, it could happen as soon as llvmdc reach
		 production quality on major platforms.


3. Destructors are not very usable as it's not possible to call in them 
methods on member objects. It makes imposible to close e.g. file in 
destructor, so there must be special API to make it. It's error prone 
and should be done automatically.

Side note: I know that this might be difficult to achieve because of way 
GC work. But it probably is doable somehow (using reference counting?)


4. Uniform syntax for templates

http://d.puremagic.com/issues/show_bug.cgi?id=1827

I will send additional post with examples of proposed syntax. I just 
need a little bit more time.


5. Anchored types

http://d.puremagic.com/issues/show_bug.cgi?id=1835

It is very usable for dupping (cloning) of objects and for call 
chaining. With this implemented, cast should appear really rarely in 
code, what will be clear win over existing major languages like e.g. 
Java, C++.

----

Extensions :-)

6. Variable arguments functions.

Current way of reading arguments is really ugly. Reading hidden 
variables to get access to function arguments breaks all rules of good 
style programming.

One way of fixing it probably would be define simple struct in Object.d 
which will keep pointer to TypeInfo and pointer to data as void*. There 
could be also used variant type as a container for arguments. Then 
function signature would look like below:

void writefln(Args[] args ...)

As a result arguments could be read as normal D type safe variadic 
argument functions. It will also allow to pass variable arguments to 
other functions, which is currently *very* inconvenient.

I think that variable arguments functions shouldn't be depreciated in 
favor of variable argument templates. At least not yet.

7. Keywords with underscores in them are ugly.

One can say that it is another example of bicycle shed color problem. 
But at least I can say that this ugliness is well established in 
*modern* programming languages. Java people will probably never agree 
that this is good notion for keywords. I unfortunately don't know what 
is status of underscores in C#, Python, Ruby.

Examples in D language:
__traits, __FILE__, __LINE__, foreach_reverse()

8. foreach() should be more universal.

It should have a form of foreach(Element element; Iterator iterator).
Other syntaxes which allows to apply different policies of iterating 
collection would be ok also. If this change would be introduced 
foreach_reverse should be just dropped from langauge.

9. Removing SFINAE.

Actually I use SFINAE in doost serializer to discover if templated 
function was defined by user in his/her class. But as I understand it is 
possible to use __traits(compile, ......) in 2.0 to get the same effect 
without all problems of SFINAE, which occurs when you make simple syntax 
error in your code...

10. 3 versions of functions for const correctness

Defining 3 versions of functions to just be const correct is definitely 
not the right way. It should be fixed.

11. Real properties

Not big priority for me, but it would be nice...


Best Regards
Marcin Kuszczak
(aarti_pl)