[Issue 15957] Disabled postblit + template mixin break opAssign with confusing error message

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=15957

Walter Bright  changed:

   What|Removed |Added

 CC||bugzi...@digitalmars.com

--- Comment #2 from Walter Bright  ---
https://github.com/dlang/dmd/pull/5713

--

[Issue 15957] Disabled postblit + template mixin break opAssign with confusing error message

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=15957

Walter Bright  changed:

   What|Removed |Added

   Hardware|x86_64  |All
 OS|Linux   |All

--

[Issue 15939] GC.collect causes deadlock in multi-threaded environment

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=15939

Walter Bright  changed:

   What|Removed |Added

 CC||bugzi...@digitalmars.com

--- Comment #8 from Walter Bright  ---
(In reply to Aleksei Preobrazhenskii from comment #7)
> I was running tests for past five days, I didn't see any deadlocks since I
> switched GC to using real-time POSIX signals (thread_setGCSignals(SIGRTMIN,
> SIGRTMIN + 1)). I would recommend to change default signals accordingly.

Since you've written the code to fix it, please write a Pull Request for it.
That way you get the credit!

--

Re: So, to print or not to print?

[xenon325 via Digitalmars-d]

On Tuesday, 26 April 2016 at 20:01:34 UTC, Andrei Alexandrescu 
wrote:

Andrei Alexandrescu  wrote:

https://github.com/dlang/phobos/pull/3971

I closed the PR as too controversial. -- Andrei


I guess it's too late, but from what I gathered from the 
comments, main controversy is about the name but not the utility 
(e.g. Adam's `substr` vs `substring` argument).


`printDelimited` and/or `printDelimitedLn`. Done.

Maybe I'm too spoiled by IDEs, but I really think we should not 
optimize for short names in std library. My (PHP and Java) IDE 
would suggest `printDelimited` after typing "prd" or even "pd".


I write such helper in every project and having it in phobos 
would be nice.


(P.S. these naming and other bikeshedding debates are pretty 
depressing in this otherwise great community)


-Alexander

Re: Russian group

[Suliman via Digitalmars-d-announce]

On Wednesday, 27 April 2016 at 02:59:50 UTC, antonio ferreira 
wrote:

On Wednesday, 2 December 2015 at 06:53:18 UTC, Suliman wrote:
On Monday, 30 November 2015 at 10:58:34 UTC, Quentin Ladeveze 
wrote:

Hi everybody,

I just created a Telegram group for dlang users : 
https://telegram.me/joinchat/BeLaugMz35ZxQUq2fks4YQ


Feel free to join !


Russian group  
https://telegram.me/joinchat/AtK90wNnU7mm0gx7yKo82w



Does russian group still exist? :/


https://telegram.me/dlangru

[Issue 15960] SetUnion should filter duplicates

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=15960

greensunn...@gmail.com changed:

   What|Removed |Added

 CC||greensunn...@gmail.com
   Severity|enhancement |normal

--

[Issue 15960] New: SetUnion should filter duplicates

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=15960

  Issue ID: 15960
   Summary: SetUnion should filter duplicates
   Product: D
   Version: D2
  Hardware: x86_64
OS: Linux
Status: NEW
  Severity: enhancement
  Priority: P1
 Component: phobos
  Assignee: nob...@puremagic.com
  Reporter: greensunn...@gmail.com

Have a look at

http://en.cppreference.com/w/cpp/algorithm/merge
http://en.cppreference.com/w/cpp/algorithm/set_union

tl;dr: SetUnion should filter for duplicates

"The difference between these two algorithms is with handling values from both
input ranges which compare equivalent (see notes on LessThanComparable). If any
equivalent values appeared n times in the first range and m times in the
second, std::merge would output all n+m occurrences whereas std::set_union
would output std::max(n, m) ones only"


```
[1,2].merge([1,3]) == [1,1,2,3]
[1,2].setUnion([1,3]) == [1,2,3]
```

--

[Issue 15959] New: core.sys.windows modules should be modified for x64

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=15959

  Issue ID: 15959
   Summary: core.sys.windows modules should be modified for x64
   Product: D
   Version: D2
  Hardware: x86_64
   URL: https://msdn.microsoft.com/en-us/library/aa383663(v=vs
.85).aspx
OS: Windows
Status: NEW
  Severity: major
  Priority: P1
 Component: druntime
  Assignee: nob...@puremagic.com
  Reporter: j...@red.email.ne.jp

core.sys.windows.* modules came with 2.070.
However, their support for x64 are not enough,
then some of those API's need modified.

The above MSDN link is the list of the APIs affected by x64.
(I've been searching for it!)

I'll send a PR later.

--

Re: Walter's Famous German Language Essentials Guide

[deadalnix via Digitalmars-d]

On Wednesday, 27 April 2016 at 02:57:47 UTC, Walter Bright wrote:
To prepare for a week in Berlin, a few German phrases is all 
you'll need to fit in, get around, and have a great time:


1. Ein Bier bitte!
2. Noch ein Bier bitte!
3. Wo ist der WC!


Some footage of Walter's last trip in Germany: 
https://www.youtube.com/watch?v=5bYMAgM42pM

Re: Russian group

[antonio ferreira via Digitalmars-d-announce]

On Wednesday, 2 December 2015 at 06:53:18 UTC, Suliman wrote:
On Monday, 30 November 2015 at 10:58:34 UTC, Quentin Ladeveze 
wrote:

Hi everybody,

I just created a Telegram group for dlang users : 
https://telegram.me/joinchat/BeLaugMz35ZxQUq2fks4YQ


Feel free to join !


Russian group  
https://telegram.me/joinchat/AtK90wNnU7mm0gx7yKo82w



Does russian group still exist? :/

Re: Directions to Ibis Hotel in Berlin from Tegel Airport

[Walter Bright via Digitalmars-d]

On 4/26/2016 12:21 PM, Andrej Mitrovic via Digitalmars-d wrote:

This is assuming you want to eat at those places while you're in
Berlin,


I'm looking forward to a bratwurst with some good senf!

Search dub via duckduckgo

[rcorre via Digitalmars-d-announce]

For those that use duckduckgo as their search engine, you can now 
search the dub package registry with the '!dub' bang.


I submitted this a while ago on a whim and it just got approved.

Re: Automatically enforce Phobos's styleguide

[Seb via Digitalmars-d]

On Tuesday, 26 April 2016 at 19:04:44 UTC, Seb wrote:

Hey all,

tl;dr: I want to pull improve Phobos code style for the greater 
good of having a bot that automatically checks the coding 
style. This should be quite useful for submitters. I hope we 
all agree that the time spent "nitpicking" is wasted, we 
overlook much (see below) and we can do better!


Agenda
--

The idea is quite simple:
1) Fix one violation for the entire codebase
2) Enable it in the bot.
3) Pick next violation and goto 1)


Great news:
1) I submitted a couple of trivial fixes (#4245, #4246, #4247)
2) The Travis bot passes :)

As mentioned I decreased the linting to a minimum, but now we do 
have it :)
Future work can fix more violations in the Phobos codebase - 
small low hanging fruits include e.g. > 120 lines or undocumented 
public methods.


For more details:
https://github.com/dlang/phobos/pull/4243

Re: DlangUI MouseEvent mouse delta

[stunaep via Digitalmars-d-learn]

I am currently handling it like this:


current = e.pos();
xdelta = current.x - previous.x;
ydelta = current.y - previous.y;
previous = current;

I'm just wondering if there is a built in solution that I missed.

Re: Line spacing for '///ditto' on the website

[Adam D. Ruppe via Digitalmars-d]

On Sunday, 24 April 2016 at 11:25:46 UTC, Nick Treleaven wrote:
There should be expand/collapse buttons for overload details so 
you can compare them simultaneously.


That's not a bad idea, but I'm probably not going to do it just 
because it doesn't fit well with my plan of separate pages for 
each function - including overloads. On the separate pages, there 
may be completely different documentation, and even if the source 
says "///ditto", the generator does things like filter out params 
that don't exist on this overload.


So I'd suggest just opening in two browser windows instead and 
positioning them side-by-side


It could also be done in Javascript. Maybe I will consider that 
later.


I think template args should not be elided completely in the 
summary, at least (...) should be shown in the signature.


Yeah, I actually agree with that now, as long as they are 
constrained (hah) by the nowrap css rule, I think they are fine. 
I am going to see about adding them on the next version.




I think there are too many line breaks, maybe this instead:

Function endsWith -> bool @anyAttributes
(alias pred, R)
(R doesThisEnd)
if (isInputRange!R &&
ifTestable!(typeof(doesThisEnd.front), unaryFun!pred))



The counterpoint to this is any page with complex individual 
arguments.


http://dpldocs.info/experimental-docs/simpledisplay.SimpleWindow.this.1.html

SimpleWindow's constructor has several parameters, most with 
default values. Take away the linebreaks there and it becomes an 
unreadable mess.


I don't have an example of long template arguments off the top of 
my head, but even cgi.d's main mixin starts to show it:


http://dpldocs.info/experimental-docs/arsd.cgi.CustomCgiMain.html

Since template arguments can have types and default values too 
(and specializers!), they can get really messy on one line as 
well.


So, putting them on one line really hurts those cases, and I 
don't think putting them on separate lines really hurts the easy 
cases (like endsWith, or std.math 
http://dpldocs.info/experimental-docs/std.math.cos.3.html it is a 
bit silly to break it down there, but it doesn't really /hurt/), 
I am erring on the side of using more space.


oh dear the table of contents there indeed is silly, I need to 
take that back out unless there's several headers.

Re: C header file: tagged enumerations

[Adam D. Ruppe via Digitalmars-d-learn]

On Tuesday, 26 April 2016 at 23:33:08 UTC, Stefan Koch wrote:

static if (win32msi >= 500) .


Won't work here because static if must have a complete 
declaration inside it, and the C pattern only has a few elements 
of the whole inside each #if.


D doesn't handle this C pattern well... you basically have to 
rewrite the whole thing for each version.


Personally, I just decide to support all of them and say the 
older versions with less declarations are less supported...

Re: C header file: tagged enumerations

[Jesse Phillips via Digitalmars-d-learn]

On Tuesday, 26 April 2016 at 23:33:08 UTC, Stefan Koch wrote:

On Tuesday, 26 April 2016 at 22:57:36 UTC, Jesse Phillips wrote:
Windows tends to have these in their header files, what is the 
best way to translate them to D?


[...]


eunm win32msi = mixin(_WIN32_MSI);

static if (win32msi >= 500) .


Sorry forgot to mention that static if doesn't allow adding 
partial declarations, always need to be complete. Or to quote the 
compiler:


"Error: basic type expected, not static"

Re: Line spacing for '///ditto' on the website

[Adam D. Ruppe via Digitalmars-d]

On Sunday, 24 April 2016 at 07:56:07 UTC, default0 wrote:
Only thing I dislike about it is that the "Overload: signature>" thing of the currently selected overload vanishes 
completely, instead of just changing color to suggest it is the 
active one you selected.


Try it now:

http://dpldocs.info/experimental-docs/std.algorithm.searching.endsWith.2.html

Also, your search currently does not list modules as search 
results (try searching base64, it will only show things like 
the Base64/Base64Impl things etc).


Huh, good catch! I split identifiers on snake_name and camelCase 
for partial matches, but never split module names on dots.



It is rebuilding its index now, you should see new results pretty 
soon. (The slow thing about it right now is I have to rebuild 
docs package-at-a-time for interlinking and nav, and I have to 
rebuild EVERYTHING for the search index. Before going beta and 
taking public packages to add to the docs, I need to make the 
regeneration incremental as it takes a while now.)


Anyhow I really should be using your docs by now, seems the 
timeframe where you hit a "this has not been implemented yet, 
sorry"-warning on half the links you click on is finally over


Aliases and single variable enums still have bugs in the 
generator (`alias a = b;` works, but `alias b a;` doesn't, and it 
thinks `enum a = 0;` is the same as `auto a = 0;`), but yeah, 
most everything else works now. I am also in the process of 
switching syntax away from Phobos' ad-hoc macros over to my new 
convenient things, so pages are still changing but most of them 
should be legible now.


I'm still short of my major goals of rewritten content and heavy 
interlinking - it can only automatically link names from the same 
module right now (it parses imports but doesn't analyze them at 
this point), but indeed, I think it is a huge step up from the 
main site.


This doc btw is describing my syntax changes:
http://dpldocs.info/experimental-docs/test.html

Re: C header file: tagged enumerations

[Stefan Koch via Digitalmars-d-learn]

On Tuesday, 26 April 2016 at 22:57:36 UTC, Jesse Phillips wrote:
Windows tends to have these in their header files, what is the 
best way to translate them to D?


[...]


eunm win32msi = mixin(_WIN32_MSI);

static if (win32msi >= 500) .

C header file: tagged enumerations

[Jesse Phillips via Digitalmars-d-learn]

Windows tends to have these in their header files, what is the 
best way to translate them to D?


https://msdn.microsoft.com/en-us/library/whbyts4t.aspx

Example below. In general a named enum is close enough to the 
same thing, but this example has additional enumerations added 
based on the preprocessor.


Assuming _WIN32_MSI is defined for compile time, what is 
recommended for creating this enum?


typedef enum tagINSTALLMESSAGE
{
// 12 others ...
INSTALLMESSAGE_INITIALIZE ,
INSTALLMESSAGE_TERMINATE  ,
INSTALLMESSAGE_SHOWDIALOG ,
#if (_WIN32_MSI >= 500)
INSTALLMESSAGE_PERFORMANCE,
#endif // (_WIN32_MSI >= 500)
#if (_WIN32_MSI >= 400)
INSTALLMESSAGE_RMFILESINUSE   ,
#endif // (_WIN32_MSI >= 400)
#if (_WIN32_MSI >= 450)
INSTALLMESSAGE_INSTALLSTART   ,
INSTALLMESSAGE_INSTALLEND ,
#endif // (_WIN32_MSI >= 450)
} INSTALLMESSAGE;

Re: Automatically enforce Phobos's styleguide

[Mark Isaacson via Digitalmars-d]

I maintain some of the linters at work. One suggestion I'd have 
(perhaps you're already on it) is that a linter that can both 
detect and prompt to auto-fix the issues is at least an order of 
magnitude more useful. People fix things more, people like the 
linters more, it avoids the fallacy of trying to get people to 
read big paragraphs of how to fix things themselves... it's just 
generally a much more awesome experience. Would recommend.

[Issue 15939] GC.collect causes deadlock in multi-threaded environment

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=15939

Vladimir Panteleev  changed:

   What|Removed |Added

 CC||c...@dawg.eu,
   ||thecybersha...@gmail.com

--

Re: Some questions on latest work

[Bill Hicks via Digitalmars-d]

On Tuesday, 26 April 2016 at 01:48:21 UTC, bigsandwich wrote:


1) This rant has nothing to do with OP's questions.  It does 
not help him.




I disagree. It does help him.  It has the potential to save him 
time and frustration.  One thing that is common among most PL 
communities is that they do not explicitly and openly communicate 
design flaws, and every other shortcoming in the language that 
has the potential to impact the user and their projects, with the 
outside world.  I can understand such a thing from a corporation 
and their marketing department, whose goal is to make money by 
manipulating people to buy their stuff, but not from a community 
of volunteers whose so-called goal is to make life easier for the 
rest of us.



2) Its a community driven project, and its free.


That's a lame excuse that's been used over and over again in FOSS 
communities, usually by those who have failed or are in the 
process of failing.  It's getting worse as more and more 
sophisticated idiots put their junk on Github and then make a big 
announcement on reddit/HN for others to start using their 
greatest inventions.


If you would rather use C++ or Rust, you know where to find 
them.


That's a kind of response one gets from Amerikans everytime 
someone criticizes the government, the educations system, the 
financial and the banking system, etc.  "If you don't like it, 
get the f**k out; this is 'Merica, the greatest country in the 
world on God's greenest earth."  The only people who think 
Amerika is great are the brain-dead and brainwashed Amerikans 
themselves.  So if you want people to use other languages, then 
stop elevating D to such high places where it doesn't belong.


On DConf, the title of Andrei's next talk should be "D's flaws 
and why you shouldn't use it."  And maybe Walter could talk about 
how "In 15 years Perl6 introduced more innovations than D in 20". 
 Think about it, D is refurbished C++, done by those with zero 
experience designing a successful programming language.  And what 
is C++?  Possibly one of the worst programming languages in the 
world.  That says something.

Re: LDC 1.0.0-beta1 has been released! Please help testing!

[Brian Schott via Digitalmars-d-announce]

On Monday, 25 April 2016 at 06:42:02 UTC, Kai Nacke wrote:
LDC 1.0.0-beta1, the LLVM-based D compiler, is available for 
download!


Using a recent build of LDC I was able to build EMSI's core data 
processing library and get it to pass all of its tests.


It also seems to handle DCD and D-Scanner correctly now.

Re: LZ4 decompression at CTFE

[Stefan Koch via Digitalmars-d-announce]

On Tuesday, 26 April 2016 at 22:07:47 UTC, MrSmith wrote:

I would like to use this instead of c++ static lib. Thanks! (I 
hope it works at runtime too).


Oh and If you could please send me a sample of a file you are 
trying to uncompress. That would be most helpful.

Re: LZ4 decompression at CTFE

[Stefan Koch via Digitalmars-d-announce]

On Tuesday, 26 April 2016 at 22:07:47 UTC, MrSmith wrote:
I would like to use this instead of c++ static lib. Thanks! (I 
hope it works at runtime too).


Sure it does, but keep in mind the c++ version is heavily 
optimized.
I would have to make a special runtime version to archive 
comparable performance I think.


That said,
I already plan to write another optimized version.

Concerning compression.
I am fairly certain I can beat the compression ratio of lz4hc in 
a few cases.

But it is going to be slower.

LZ4 decompression at CTFE

[Stefan Koch via Digitalmars-d-announce]

Hello,

originally I want to wait with this announcement until DConf.
But since I working on another toy. I can release this info early.

So as per title. you can decompress .lz4 flies created by the 
standard lz4hc commnadline tool at compile time.


No github link yet as there is a little bit of cleanup todo :)

Please comment.

Re: LZ4 decompression at CTFE

[MrSmith via Digitalmars-d-announce]

On Tuesday, 26 April 2016 at 22:05:39 UTC, Stefan Koch wrote:

Hello,

originally I want to wait with this announcement until DConf.
But since I working on another toy. I can release this info 
early.


So as per title. you can decompress .lz4 flies created by the 
standard lz4hc commnadline tool at compile time.


No github link yet as there is a little bit of cleanup todo :)

Please comment.


I would like to use this instead of c++ static lib. Thanks! (I 
hope it works at runtime too).

Re: Some questions on latest work

[Bill Hicks via Digitalmars-d]

On Tuesday, 26 April 2016 at 02:33:41 UTC, Andrei Alexandrescu 
wrote:


That's a pretty awesome rant! Bill, could you please email me 
your mailing address? I'd be glad to send you a DConf T-shirt. 
Thanks! -- Andrei


Quitting a well paying job at Facebook to peruse a hobby sounds 
like something a person going through midlife crisis would do.  
You may keep the T-shirt.  I suggest you smoke some DMT (and have 
a breakthrough), or have a few Ayahuasca sessions.  If that 
doesn't set you off on a path to the greatest positive impact, 
then nothing ever will.  Everything you've desired to achieve 
with D is a construct of your ego, and nothing more.

Re: So, to print or not to print?

[Solomon E via Digitalmars-d]

On Tuesday, 26 April 2016 at 21:11:22 UTC, Solomon E wrote:

...
writesln(a, b); // I would expect does the same as
writefln("%s %s", a, b);

alias print = writesln!(separator="\t");
print(a, b); // now with tab separation

...


Sorry about using a named template argument when that isn't a 
thing apparently.


writesln!"\t"("A", "B"); // tab separation

void print(string separator = "\t", string eol = "\n", S...)(auto 
ref S args)

{
writesln!(separator, eol, S)(args);
}
print("A", "B"); // now with tab separation

Those lines successfully run, and I don't know how to define a 
custom "print" shorter yet.

[Issue 7417] One-definition rule for version specification - allow version expressions

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=7417

Witold Baryluk  changed:

   What|Removed |Added

 CC||bary...@smp.if.uj.edu.pl

--- Comment #6 from Witold Baryluk  ---
Hi. Any update on this.

I was just trying to compiled phobos using gdc on arm64, and of course first
thing that failed was a static assert in
libdruntime/core/sys/posix/sys/socket.d that do have about 10 different semi
duplicated version branches.

I would really want to say:

version (ARM || AArch64 || PPC || PPC64 || MIPS32 || MIPS64 || X86 || X86_64) {
  ...
} else version (SomethingSpecial) {
  ...
} else {
  static assert(0);
}


That would be good enough in most cases.

Support for more elaborate conditions would be nice too.

instead of

version (A) {
} else {
  somethign special.
}


version (!A) {
  something special.
}


or 

version (A) {
version (B) {
  something.
}
}
version (A && B) {
  something.
}

It is probably possible to implement what I want using mixing and putting
common code in the template, and then expand

version (ARM || AArch64 || PPC || PPC64 || MIPS32 || MIPS64 || X86 || X86_64) {


into separate branches with mixed-in template. Still I fell, explicit booleans
support on versions would be nicer.

BTW. The mentioned file also shows almost the same enums in the OSX and FreeBSD
branches, so maybe in this case it is worth doing this via mixin, as the OSX
and FreeBSD branches cannot be really folded easily into one version (OSX ||
FreeBSD) branch. Same with Android (with do have same enum values as Linux).

--

Re: Directions to Ibis Hotel in Berlin from Tegel Airport

[Nemanja Boric via Digitalmars-d]

On Tuesday, 26 April 2016 at 19:21:13 UTC, Andrej Mitrovic wrote:
It's really not so bad anymore as it used to be. Credit cards 
are accepted in most stores or supermarkets, even "Netto" which 
is a discount-store and which started accepting Visa just last 
year. Other stores like "Real" and "Kaisers" will accept Visa, 
even many small shops will accept it.


Then again the Burger King at Alexanderplatz will for some 
reason *not* accept any credit card, while the McDonalds which 
is ~50 meters away will.


This is assuming you want to eat at those places while you're 
in Berlin, obviously there's great food here that you could try 
rather than go to the familiar fast-food chains.. If you're 
going to go for a döner kebab prepare some cash!


In some cases they might ask you for your ID (e.g. passport).

On 4/26/16, Johannes Pfau via Digitalmars-d 
 wrote:

Am Tue, 26 Apr 2016 12:25:41 +
schrieb Kagamin :


On Monday, 25 April 2016 at 09:16:11 UTC, Iain Buclaw wrote:
> Germany is a cash-in-hand country.  Credit cards are 
> rejected in most places that I've tried.


You mean debit cards are accepted? Anyway why credit cards? 
Aren't credit money more expensive than debit? The overdraft 
limit is just a fixed offset from zero and you pay extra 
interest, one could just imagine zero balance at his 
preferred offset and keep it there.


The girocard (sometimes called EC card) debit card system is 
accepted at most places: 
https://en.wikipedia.org/wiki/Girocard IIRC you need a german 
bank account though to own such a card ;-)


I was today to TXL, so I took some pictures while riding home (I 
was sitting on a passenger side).


First, here are the routes for 109 and U7:

https://www.bvg.de/images/content/linienverlaeufe/LinienverlaufBus109.pdf
https://www.bvg.de/images/content/linienverlaeufe/LinienverlaufU7.pdf

This is the U-Bahnhof Jakob-Keiser-Platz:

http://imgur.com/nCBxOho

This is the pink-orange building just before it (I took a picture 
when I passed it):


http://imgur.com/zrQw6Fn

In the bus, there's a display showing next station and a voice 
(in German, but even I can recognize the name of the station) 
telling the name of the next station. It's needed to indicate 
that you're going off the bus (this caught me when I was a new 
one) which needs to be pressed *before* the bus arrive to the 
station (if somebody has pressed it, you'll see red STOP on the 
right corner of the display) by pressing one of the green tasters 
on the yellow bars. Sorry for the potato quality:


http://imgur.com/gTzEtxh

And *bonus level*. If you didn't get off at U-Bahnhof 
Jakob-Keiser-Platz, 15 minutes after, 109 will get to U Bahnhof 
Adenauerplatz where you can catch U7 again (just after it turns 
right after S-Bahnhof Charlottenburg):


http://imgur.com/0TZWI7P

Re: Checking if an Integer is an Exact Binary Power

[Timon Gehr via Digitalmars-d]

On 26.04.2016 17:27, Xinok wrote:

On Monday, 25 April 2016 at 15:35:14 UTC, Dominikus Dittes Scherkl wrote:

On Monday, 25 April 2016 at 15:27:02 UTC, Xinok wrote:

Brute force.

http://dpaste.dzfl.pl/882d7cdc5f74

Yeah. And your test spares the failed case int.min (0x8000),
because in this case x & -x is negative, but of cause x>>>1 is
positive, so it returns false despite -(2^^31) is in fact a power of
two. So this requires an extra cast to work correct (in fact no big
difference in the assembly):

return (Unsigned!T)(x & -x) > (Unsigned!T)(x >>> 1);


How is it wrong? Negative numbers are NOT powers of two (unless you have
an imaginary/complex exponent), so it's still correct to return false
for -int.min. Should it not?

http://www.wolframalpha.com/input/?i=solve+2^n+%3D+-%282^31%29+for+n


static assert(2^^31==int.min); // :o)

Re: So, to print or not to print?

[Jon D via Digitalmars-d]

On Tuesday, 26 April 2016 at 16:30:22 UTC, Jonathan M Davis wrote:
On Tuesday, April 26, 2016 12:18:11 cym13 via Digitalmars-d 
wrote:
Finally it doesn't bring much. One learns writeln, laments a 
bit that it doesn't put spaces itself then just accepts it.


I confess that I was very surprised to find out that writeln 
worked with multiple arguments.


In my initial look at D I would have appreciated print. However, 
at least part of the reason is that it was a while before I knew 
writefln existed. After finding it (and discovering that writeln 
takes multiple arguments), having the functionality of print was 
less an issue.


It's not easy to reconstruct why it took me a while to discover 
writefln, but perhaps finding places to show it off in 
introductory material would help others find it more quickly.


--Jon

Re: Simple and effective approaches to constraint error messages

[Timon Gehr via Digitalmars-d]

On 26.04.2016 13:26, Marc Schütz wrote:


Currently, there is no boolean short-cut evaluation in template
constraints, see:

 bool foo()() {
 pragma(msg, "foo");
 return true;
 }

 bool bar()() {
 pragma(msg, "bar");
 return true;
 }

 void main() {
 static assert(__traits(compiles, foo() || bar()));
 }

Prints "foo" and "bar", even though bar() wouldn't need to be evaluated
anymore after foo() returned true.


There sometimes is short-cut evaluation. This only prints "Foo":

template Foo(){
pragma(msg, "Foo");
enum Foo=true;
}
auto bar()(){
pragma(msg, "bar");
return true;
}
void main(){
static assert(Foo!()||bar());
}

I don't see the point of the different behaviour for those cases.

[Issue 8384] std.conv.to should allow conversion between any pair of string/wstring/dstring/char*/wchar*/dchar*

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=8384

--- Comment #25 from github-bugzi...@puremagic.com ---
Commits pushed to master at https://github.com/dlang/phobos

https://github.com/dlang/phobos/commit/60a233372a96abab810f030b4e3ff494987aa25e
Partial fix of Issue 8384 - std.conv.to should allow conversion between any
pair of string/wstring/dstring/char*/wchar*/dchar*

https://github.com/dlang/phobos/commit/22c7f11265d62ad1ac387bc9aaa90b742f9563b2
Merge pull request #4199 from Biotronic/fix-8384

Partial fix of Issue 8384 - std.conv.to should allow conversion betwe…

--

Re: So, to print or not to print?

[Era Scarecrow via Digitalmars-d]

On Tuesday, 26 April 2016 at 12:38:06 UTC, Jonathan M Davis wrote:
On Tuesday, April 26, 2016 08:50:23 ixid via Digitalmars-d 
wrote:

and seem to think
'print(a, b, c);' is going to confuse people more than 
'writefln("%s %s %s", a, b, c);' which is ridiculous.


Honestly, I think that writefln is way clearer than print. 
Certainly, if you're familiar with printf, it's pretty obvious 
what writefln does with the possible confusion over whether it 
prints a newline or not (and the ln in the name is there to 
tell you that), whereas it's not at all obvious what print is 
going to do without looking at the docs.


 We could always use C++ streams! They are perfectly clear what 
they're doing, right?


 stdout << a << " " << b << " " << c << endl;

 Seriously, a formatting line may only be confusing at first, but 
it's something you need to learn at some point. I don't ever want 
to rely on something as ugly as streams. C had printf; which was 
print, with an f! and that was good enough for everything! (I 
feel like I'm quoting Garfield now)


 Not that long ago when I was getting into D, I used printf more, 
then when I memorized writeln I used it a lot more. It's really 
not that bad. More people should sit down and read the damn 
documentation (mind you I've read about half of it, and I need to 
start over now since it's been so long).

Re: So, to print or not to print?

[Andrei Alexandrescu via Digitalmars-d]

Andrei Alexandrescu  wrote:
> https://github.com/dlang/phobos/pull/3971
> 
> Walter and I were talking this morning that there should be a high 
> barrier of entry for one-liners in Phobos. The "print" function is 
> technically a one-liner (i.e. writefln with the appropriate format 
> string). On the other hand, it may be convivial enough to warrant 
> inclusion, and saves us from embarrassing things such as producing 
> meaningless output when numbers are printed together.
> 
> There's been a bit of churn in the PR comments regarding the utility of 
> "print", and discussion diverged into other functions such as "dump" 
> etc. Keeping it on topic: any strong cons and pros regarding the 
> function? I want to either merge or close the PR and move on.
> 
> 
> Thanks,
> 
> Andrei
> 

I closed the PR as too controversial. -- Andrei

Re: Some questions on latest work

[Era Scarecrow via Digitalmars-d]

On Tuesday, 26 April 2016 at 18:16:42 UTC, Joakim wrote:

On Tuesday, 26 April 2016 at 13:55:23 UTC, ag0aep6g wrote:
Please don't bash on other languages, especially when they're 
perceived as competition. It reflects badly on the D community.


He gave very specific criticism, along with a code sample, then 
made a prediction, followed by suggesting another competing 
language that might do better.


To be honest when I looked at the code I thought it was really 
hard to read and it was C++, it wasn't until I noted we were 
talking about rust that I looked at it again, but it hurts my 
eyes and my head...

Re: Some questions on latest work

[deadalnix via Digitalmars-d]

On Tuesday, 26 April 2016 at 19:39:01 UTC, ag0aep6g wrote:

 None of that is the usual content-free fanboy "bashing."


I don't agree. I don't see any content to speak of.


You are talking a lot for someone who sees nothing to speak of.

Re: Checking if an Integer is an Exact Binary Power

[Era Scarecrow via Digitalmars-d]

On Tuesday, 26 April 2016 at 18:04:53 UTC, deadalnix wrote:
You got to explain me how you end up with a negative number by 
multiplying 2 by 2 a bunch of time.


You gotta scrawl your numbers down badly so one of the 2's looks 
like a minus sign. Or go so large that the universe caves in on 
itself.

Re: String lambdas

[Jack Stouffer via Digitalmars-d]

On Tuesday, 26 April 2016 at 17:58:22 UTC, Andrei Alexandrescu 
wrote:

https://github.com/dlang/phobos/pull/3882

I just closed with some regret a nice piece of engineering. 
Please comment if you think string lambdas have a lot of 
unexploited potential.


I'm of the opinion that string lambdas must go. I started, and I 
really should finish it at some point, removing string lambdas 
from the documentation: https://github.com/dlang/phobos/pull/3800


I think that the drawback you mentioned does not outweigh the 
benefits gained from using actual lambdas.

Re: Some questions on latest work

[ag0aep6g via Digitalmars-d]

On 26.04.2016 20:16, Joakim wrote:

He gave very specific criticism,


This is not "very specific criticism": "Are you joking? When I am 
reading it's code my eyes begin to bleed. It's syntax is terrible. [...] 
Do you really think that modern language should like this?"



along with a code sample,


He gave a code sample, yes. He didn't point out what he dislikes about 
it. He didn't contrast it with another language.



then made a prediction,


You skipped the part where he puts puts down Rust "fan boys", saying 
they don't even understand Rust code.


His "prediction" is the death of Rust. In my opinion, calling death upon 
competing projects is bad form.


[...]

 None of that is the usual content-free fanboy "bashing."


I don't agree. I don't see any content to speak of.

Re: Directions to Ibis Hotel in Berlin from Tegel Airport

[Andrej Mitrovic via Digitalmars-d]

It's really not so bad anymore as it used to be. Credit cards are
accepted in most stores or supermarkets, even "Netto" which is a
discount-store and which started accepting Visa just last year. Other
stores like "Real" and "Kaisers" will accept Visa, even many small
shops will accept it.

Then again the Burger King at Alexanderplatz will for some reason
*not* accept any credit card, while the McDonalds which is ~50 meters
away will.

This is assuming you want to eat at those places while you're in
Berlin, obviously there's great food here that you could try rather
than go to the familiar fast-food chains.. If you're going to go for a
döner kebab prepare some cash!

In some cases they might ask you for your ID (e.g. passport).

On 4/26/16, Johannes Pfau via Digitalmars-d  wrote:
> Am Tue, 26 Apr 2016 12:25:41 +
> schrieb Kagamin :
>
>> On Monday, 25 April 2016 at 09:16:11 UTC, Iain Buclaw wrote:
>> > Germany is a cash-in-hand country.  Credit cards are rejected
>> > in most places that I've tried.
>>
>> You mean debit cards are accepted? Anyway why credit cards?
>> Aren't credit money more expensive than debit? The overdraft
>> limit is just a fixed offset from zero and you pay extra
>> interest, one could just imagine zero balance at his preferred
>> offset and keep it there.
>
> The girocard (sometimes called EC card) debit card system is accepted at
> most places: https://en.wikipedia.org/wiki/Girocard IIRC you need a
> german bank account though to own such a card ;-)
>

Re: String lambdas

[Jonathan M Davis via Digitalmars-d]

On Tuesday, April 26, 2016 13:58:22 Andrei Alexandrescu via Digitalmars-d 
wrote:
> https://github.com/dlang/phobos/pull/3882
>
> I just closed with some regret a nice piece of engineering. Please
> comment if you think string lambdas have a lot of unexploited potential.

Well, they're nicer than the "new" lambda syntax for really short stuff like
"a == b" or "a != b", but beyond that, the newer syntax mostly does what the
string lambdas were trying to do. And if your lambda gets very long, it
really should be replaced with something like a nested function anyway.
Pretty much anything complicated shouldn't be a lambda, or it risks being
unmaintainable. So, while that PR was indeed a nice piece of engineering, it
seems to be solving a problem that really shouldn't be solved with lambdas
anyway.

> One thing we really need in order to 100% replace string lambdas with
> lambdas is function equivalence. Right now we're in the odd situation
> that SomeTemplate!((a, b) => a < b) has distinct types, one per
> instantiation.

Once that's solved, we can consider deprecating string lambdas, but
equivalence is indeed the one killer feature that non-string lambdas lack.
However, from what I recall of discussions on that, it sounded like it was
going to be pretty nasty to implement. :(

- Jonathan M Davis

[Issue 15111] hashOf fails for structs that have an alias this to a dynamic array

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=15111

--- Comment #1 from github-bugzi...@puremagic.com ---
Commits pushed to master at https://github.com/dlang/druntime

https://github.com/dlang/druntime/commit/3af285fea29e7bbe2bea9b4fcb4b93f1ecb72755
fix issue 15111 - hashOf fails for structs that have an alias this to a dynamic
array

https://github.com/dlang/druntime/commit/2d8b0a5901bde46d3f773ad1a22cd3780306067c
Merge pull request #1536 from BBasile/issue-15111

fix issue 15111 - hashOf fails for structs that have an alias this to a dynamic
array

--

[Issue 15111] hashOf fails for structs that have an alias this to a dynamic array

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=15111

github-bugzi...@puremagic.com changed:

   What|Removed |Added

 Status|NEW |RESOLVED
 Resolution|--- |FIXED

--

Re: Automatically enforce Phobos's styleguide

[tsbockman via Digitalmars-d]

On Tuesday, 26 April 2016 at 19:04:44 UTC, Seb wrote:
As expected a styleguide without a automatically enforcing it, 
leaks ...


It's not so much a matter of "leaks" - rather, much of DMD, 
D-runtime, and Phobos pre-date the style rules, and so never 
attempted to follow them in the first place.


Indeed, some of the rules we have now were chosen simply by 
surveying the existing eclectic code base to determine which 
conventions were *most common* - in some cases by slim margins...

DlangUI MouseEvent mouse delta

[stunaep via Digitalmars-d-learn]

I am trying to know how much the mouse moves when clicking down 
on a certain widget, but I can't figure out how. I noticed only a 
mouse wheel delta property and nothing for the mouse pointer x,y 
deltas since the click. I am looking to do something such as


if(e.lbutton().isDown() && !e.rbutton().isDown()) {
pitch -= e.dy();
}

Automatically enforce Phobos's styleguide

[Seb via Digitalmars-d]

Hey all,

tl;dr: I want to pull improve Phobos code style for the greater 
good of having a bot that automatically checks the coding style. 
This should be quite useful for submitters. I hope we all agree 
that the time spent "nitpicking" is wasted, we overlook much (see 
below) and we can do better!


Agenda
--

The idea is quite simple:
1) Fix one violation for the entire codebase
2) Enable it in the bot.
3) Pick next violation and goto 1)

First violation: space between operators


Can be easily fixed by running this:

```
sed -i "s/switch(/switch (/" **/*.d
sed -i "s/foreach(/foreach (/" **/*.d
sed -i "s/foreach_reverse(/foreach_reverse (/" **/*.d
sed -i "s/while(/while (/" **/*.d
sed -i "s/if(/if (/" **/*.d
```

I started with some PRs (one is way to large to review):

https://github.com/dlang/phobos/pull/4239
https://github.com/dlang/phobos/pull/4240
https://github.com/dlang/phobos/pull/4241
https://github.com/dlang/phobos/pull/4242

How big is this change?
---

grep -E "(for|foreach|foreach_reverse|if|while)\(" $(find . 
-name '*.d') | wc -l


3505

As expected a styleguide without a automatically enforcing it, 
leaks ...


Disadvantages
-

This potentially might create some troubles with forks or pending 
PRs.


-> If anyone objects the introduction of automatic linting to 
Phobos, please raise your voice!

Re: So, to print or not to print?

[Andrei Alexandrescu via Digitalmars-d]

On 04/26/2016 02:29 PM, TheGag96 wrote:

On Tuesday, 26 April 2016 at 14:33:42 UTC, tn wrote:

Maybe the name of the function should then be "writes" and/or
"writesln" (instead of "print"), so that it can at least be found from
the same place in the documentation as other related functions. The
naming scheme would then also be consistent with the rest of the
write/writef-family. (Here -s stands for "separated/spaced" just as -f
stands for "formatted" etc.)


I really like this idea. Much better than just "print", and maybe even
better than "dump".


Can't it be confused with a verb? -- Andrei

Re: So, to print or not to print?

[TheGag96 via Digitalmars-d]

On Tuesday, 26 April 2016 at 14:33:42 UTC, tn wrote:
Maybe the name of the function should then be "writes" and/or 
"writesln" (instead of "print"), so that it can at least be 
found from the same place in the documentation as other related 
functions. The naming scheme would then also be consistent with 
the rest of the write/writef-family. (Here -s stands for 
"separated/spaced" just as -f stands for "formatted" etc.)


I really like this idea. Much better than just "print", and maybe 
even better than "dump".

Re: Some questions on latest work

[Joakim via Digitalmars-d]

On Tuesday, 26 April 2016 at 13:55:23 UTC, ag0aep6g wrote:

On 26.04.2016 10:20, Suliman wrote:

Do you really think that modern language should like this?

I talked with a lot of rust fun-boys. Most of them do not 
understand do

not understand the code of their favourite language.

Rust will die when Mozilla will move to WebKit. I much more 
believe in

Swift success, that that Rust have any future.


Please don't bash on other languages, especially when they're 
perceived as competition. It reflects badly on the D community.


He gave very specific criticism, along with a code sample, then 
made a prediction, followed by suggesting another competing 
language that might do better.  None of that is the usual 
content-free fanboy "bashing."  There is nothing wrong with 
occasional criticism of the competition, as long as we don't 
overdo it, either in frequency or by exaggerating.

[Issue 15958] Missing extern(Windows) of core.sys.windows functions

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=15958

--- Comment #2 from github-bugzi...@puremagic.com ---
Commit pushed to master at https://github.com/dlang/druntime

https://github.com/dlang/druntime/commit/7d84c696f208ae562e769e0321ace8688a0131bd
Merge pull request #1550 from qchikara/pr-winapi-linkage

Fix Issue 15958 - Missing extern(Windows) of core.sys.windows functions

--

Re: Checking if an Integer is an Exact Binary Power

[deadalnix via Digitalmars-d]

On Tuesday, 26 April 2016 at 08:12:02 UTC, Dominikus Dittes 
Scherkl wrote:

On Monday, 25 April 2016 at 22:42:38 UTC, deadalnix wrote:
x & -x is the smallest power of 2 that divides x. Basically, 
if x = 1000 , x & -x = 1000 . This is easy to proves 
considering -x = ~x + 1 .


Now, x >> 1 will be of the form 0100 . If one of these 
digit is one, then (x >> 1) >= (x & -x) . If they are all 
zeros, (x >> 1) < (x & -x) which is the case where you have a 
power of 2.


0 is a special case, can it can be checked that the function 
return false for this specific input.


This looks like it is correct.


Yes. Except for the case 0x8000 (= int.min), because this 
is negative so NOT smaller than 0x4000 (= int.min>>>1), 
which is considered positive.
So the algorithm doesn't work for signed integers (without 
extra cast).


You got to explain me how you end up with a negative number by 
multiplying 2 by 2 a bunch of time.

String lambdas

[Andrei Alexandrescu via Digitalmars-d]

https://github.com/dlang/phobos/pull/3882

I just closed with some regret a nice piece of engineering. Please 
comment if you think string lambdas have a lot of unexploited potential.


One thing we really need in order to 100% replace string lambdas with 
lambdas is function equivalence. Right now we're in the odd situation 
that SomeTemplate!((a, b) => a < b) has distinct types, one per 
instantiation.



Andrei

Re: Directions to Ibis Hotel in Berlin from Tegel Airport

[Johannes Pfau via Digitalmars-d]

Am Tue, 26 Apr 2016 12:25:41 +
schrieb Kagamin :

> On Monday, 25 April 2016 at 09:16:11 UTC, Iain Buclaw wrote:
> > Germany is a cash-in-hand country.  Credit cards are rejected 
> > in most places that I've tried.  
> 
> You mean debit cards are accepted? Anyway why credit cards? 
> Aren't credit money more expensive than debit? The overdraft 
> limit is just a fixed offset from zero and you pay extra 
> interest, one could just imagine zero balance at his preferred 
> offset and keep it there.

The girocard (sometimes called EC card) debit card system is accepted at
most places: https://en.wikipedia.org/wiki/Girocard IIRC you need a
german bank account though to own such a card ;-)

Re: Lazy Generation of Random Sequence

[Seb via Digitalmars-d-learn]

On Tuesday, 26 April 2016 at 17:38:33 UTC, Nordlöw wrote:

On Tuesday, 26 April 2016 at 11:09:42 UTC, Seb wrote:
Btw if you do random generation at the moment, you should 
always be aware that it's super-easy to do an implicit copy if 
you pass around the rndGen


So should I pass it by ref or const ref then?


I guess both work fine, but this was just a warning for other 
case.
The example that @WebDrake mentioned on his slides can happen too 
easily - a reason why we should fix it (which is on my agenda).

Re: Lazy Generation of Random Sequence

[Nordlöw via Digitalmars-d-learn]

On Tuesday, 26 April 2016 at 11:09:42 UTC, Seb wrote:
Btw if you do random generation at the moment, you should 
always be aware that it's super-easy to do an implicit copy if 
you pass around the rndGen


So should I pass it by ref or const ref then?

Re: Lazy Generation of Random Sequence

[Nordlöw via Digitalmars-d-learn]

On Tuesday, 26 April 2016 at 17:38:33 UTC, Nordlöw wrote:

On Tuesday, 26 April 2016 at 11:09:42 UTC, Seb wrote:
Btw if you do random generation at the moment, you should 
always be aware that it's super-easy to do an implicit copy if 
you pass around the rndGen


So should I pass it by ref or const ref then?


Doh. Const ref is of no use... just by ref then, right?

Re: Checking if an Integer is an Exact Binary Power

[Temtaime via Digitalmars-d]

On Tuesday, 26 April 2016 at 16:53:00 UTC, tsbockman wrote:

On Tuesday, 26 April 2016 at 14:37:46 UTC, Marco Leise wrote:

Can we just use __traits(hasTargetFeature, "popcnt") already
and get rid of _popcnt?


No, because DMD does not currently support setting SSE4 as the 
minimum target. Thus, `__traits(hasTargetFeature, "popcnt")` 
must always return `false` at compile time.


As for LDC and GDC - both already treat `popcnt()` as an 
intrinsic, and don't need your proposed change.


It's strange why it emits an branch.

http://goo.gl/jJbSYd
Det version doesn't use cmp and should be fast.

Re: Checking if an Integer is an Exact Binary Power

[tsbockman via Digitalmars-d]

On Tuesday, 26 April 2016 at 14:37:46 UTC, Marco Leise wrote:

Can we just use __traits(hasTargetFeature, "popcnt") already
and get rid of _popcnt?


No, because DMD does not currently support setting SSE4 as the 
minimum target. Thus, `__traits(hasTargetFeature, "popcnt")` must 
always return `false` at compile time.


As for LDC and GDC - both already treat `popcnt()` as an 
intrinsic, and don't need your proposed change.

Re: Minecraft written in D - on Android

[Vadim Lopatin via Digitalmars-d-announce]

On Tuesday, 26 April 2016 at 14:25:05 UTC, Benjamin Thaut wrote:

On Tuesday, 26 April 2016 at 08:42:21 UTC, Vadim Lopatin wrote:
Demo of DlangUI Scene3D engine - Minecraft-like voxel 
rendering - is available for Android/ARM.


Post screenshots please.


Screenshot from my android device:

http://imgur.com/gallery/7wVBk8E

Re: Minecraft written in D - on Android

[Vadim Lopatin via Digitalmars-d-announce]

On Tuesday, 26 April 2016 at 14:05:19 UTC, WebFreak001 wrote:

On my android device it says "Failed to parse package"

Also where is the source at so I can run dub manually?


Dub build is available only for desktop.

For Android, clone repository

git clone --recursive https://github.com/buggins/dlangui.git

Go to dlangui/examples/dminer/android_project

Edit paths in file android_build_config.mk

export DLANGUI_DIR=$HOME/src/d/dlangui
export NDK=$HOME/android-ndk-r11c
export SDK=$HOME/android-sdk-linux
export LDC=$HOME/ldc2-android-arm-0.17.0-alpha2-linux-x86_64
export NDK_ARCH=x86_64
export JAVA_HOME=/usr/lib/jvm/java-8-oracle/

To build package, you will need Android NDK, SDK, LDC2 for 
android.
In Android SDK manager, download platform android-19 (Android 
4.4.X)


Build is tested only on Linux X64.

More build instructions:

https://github.com/buggins/dlangui/blob/master/examples/dminer/android_project/README.md

Re: So, to print or not to print?

[Jonathan M Davis via Digitalmars-d]

On Tuesday, April 26, 2016 12:18:11 cym13 via Digitalmars-d wrote:
> Finally it doesn't bring much. One learns writeln, laments a bit
> that it doesn't put spaces itself then just accepts it.

I confess that I was very surprised to find out that writeln worked with
multiple arguments. I fully expected writeln to just print what you give it
followed by a newline, whereas writefln would take a format string and act
like printf except for how %s works with everything, and it adds a newline.
I never would have expected any kind of print function that would print
multiple arguments without a format string.

- Jonathan M Davis

Re: So, to print or not to print?

[Adam D. Ruppe via Digitalmars-d]

On Tuesday, 26 April 2016 at 15:55:54 UTC, Andrei Alexandrescu 
wrote:
Deja vu all over again. Where's the exchange where that 
argument got destroyed? -- Andrei


Your attempt at destruction bounced off the thick armor of my 
superior argument!


Here's your comment from the other thread:

https://github.com/dlang/phobos/pull/3971#issuecomment-183368836

"The way I see it is their charters are different, one is not 
better or worse than the other."


You can say exactly the same thing about substr and substring - 
their charters are different, one works by index and one by 
length! The question is: which one is which? Why is it print that 
adds spaces instead of write?


Why is print not to printf what write is to writef?


It is just too similar.

BTW ruby and php have print functions. Neither output spaces...

Re: Simple and effective approaches to constraint error messages

[Meta via Digitalmars-d]

On Tuesday, 26 April 2016 at 15:56:55 UTC, Andrei Alexandrescu 
wrote:

On 04/26/2016 11:35 AM, Meta wrote:
The nice part about 1 is that every constraint gets it for 
free.


Only if in CNF, otherwise needs changed. -- Andrei


True, but I bet the majority of template constraints are in this 
form. The wiki page you linked also says that clauses that are 
not in CNF can be rewritten in CNF, but doing that automatically 
in the compiler would probably be difficult, bug-ridden, and 
annoying for end users.


Are you familiar with Nim's implementation of concepts? I think 
somebody actually implemented something close to this in D using 
inheritance and introspection.


http://nim-lang.org/docs/manual.html#generics-concepts

Re: So, to print or not to print?

[Seb via Digitalmars-d]

On Tuesday, 26 April 2016 at 14:33:42 UTC, tn wrote:
On Tuesday, 26 April 2016 at 12:52:13 UTC, Andrei Alexandrescu 
wrote:

On 04/26/2016 08:18 AM, cym13 wrote:

[...]


"When you want spaces between arguments and when you don't".

We've been over this. Nobody asks when they should use writef 
over writeln or readf over readln (which also share a common 
role with common features).


Maybe the name of the function should then be "writes" and/or 
"writesln" (instead of "print"), so that it can at least be 
found from the same place in the documentation as other related 
functions. The naming scheme would then also be consistent with 
the rest of the write/writef-family. (Here -s stands for 
"separated/spaced" just as -f stands for "formatted" etc.)


I like the `writes` idea!
Could be a good compromise ;-)

Re: So, to print or not to print?

[Andrei Alexandrescu via Digitalmars-d]

On 04/26/2016 09:50 AM, cym13 wrote:

On Tuesday, 26 April 2016 at 12:46:09 UTC, Andrei Alexandrescu wrote:

On 04/26/2016 04:50 AM, ixid wrote:

Please find an example of a newcomer who would be confused by print.
This is an objectionable argument because none of the people making it
are newcomers, you're using an entirely theoretical newcomer as your
argument, and seem to think 'print(a, b, c);' is going to confuse people
more than 'writefln("%s %s %s", a, b, c);' which is ridiculous.


Let me also add that the very request came from a former newcomer. --
Andrei


Well except maybe for you and Walter I think we're all former newcomers.


Good point but you know I mean "recently former" :o). -- Andrei

Re: So, to print or not to print?

[Andrei Alexandrescu via Digitalmars-d]

On 04/26/2016 09:56 AM, Adam D. Ruppe wrote:

On Tuesday, 26 April 2016 at 12:52:13 UTC, Andrei Alexandrescu wrote:

"When you want spaces between arguments and when you don't".


As I have said before, other languages have tried this kind of thing...
and they aren't remembered well for it.

substr vs substring in javascript is the first big example. Similar
name, subtle difference.


Deja vu all over again. Where's the exchange where that argument got 
destroyed? -- Andrei

Re: Simple and effective approaches to constraint error messages

[Andrei Alexandrescu via Digitalmars-d]

On 04/26/2016 11:35 AM, Meta wrote:

The nice part about 1 is that every constraint gets it for free.


Only if in CNF, otherwise needs changed. -- Andrei

Re: Compare lambda expressions

[Meta via Digitalmars-d-learn]

There's no way to do this in D. There have been several proposals 
but nothing implemented as of yet.

Re: So, to print or not to print?

[Meta via Digitalmars-d]

On Monday, 25 April 2016 at 19:35:04 UTC, Andrei Alexandrescu 
wrote:

https://github.com/dlang/phobos/pull/3971

Walter and I were talking this morning that there should be a 
high barrier of entry for one-liners in Phobos. The "print" 
function is technically a one-liner (i.e. writefln with the 
appropriate format string). On the other hand, it may be 
convivial enough to warrant inclusion, and saves us from 
embarrassing things such as producing meaningless output when 
numbers are printed together.


There's been a bit of churn in the PR comments regarding the 
utility of "print", and discussion diverged into other 
functions such as "dump" etc. Keeping it on topic: any strong 
cons and pros regarding the function? I want to either merge or 
close the PR and move on.



Thanks,

Andrei


Python users are only a subset of new users coming to D, and as 
far as I know it is the only big language where such a `print` 
primitive exists with the semantics of putting spaces between 
each item printed. Ruby also has `print` but it does not put 
spaces between arguments; it adds a newline after each argument. 
So which behaviour should we copy?


None of the other big languages, C, C++, Javascript, Java, C#, 
Scala, Groovy, et al., have a `print` function that matches the 
semantics of Python's print (nor Ruby's). Why add yet another IO 
function that will only help very inexperienced beginners coming 
from a single (popular, granted) language? I'm all for making the 
D experience easy for beginners, but this is not a low-hanging 
fruit. It's just rotten.

Re: Simple and effective approaches to constraint error messages

[Meta via Digitalmars-d]

On Monday, 25 April 2016 at 17:52:58 UTC, Andrei Alexandrescu 
wrote:

Idea #2: Allow custom error messages


The basic idea here is to define pragma(err, "message") as an 
expression that formats "message" as an error and returns 
false. Then we can write:


R find(R, E)(R range, E elem)
if ((isInputRange!R || pragma(err, R.stringof~" must be an 
input range")

   &&
   (is(typeof(range == elem) == bool) || pragma(err, "..."))

Now, when printing the failed candidate, the compiler adds the 
error message(s) produced by the failing constraint.


The problem with this is verbosity - e.g. we almost always want 
to write the same message when isInputRange fails, so naturally 
we'd like to encapsulate the message within isInputRange. This 
could go as follows. Currently:


template isInputRange(R)
{
enum bool isInputRange = is(typeof(
(inout int = 0)
{
R r = R.init; // can define a range object
if (r.empty) {}   // can test for empty
r.popFront(); // can invoke popFront()
auto h = r.front; // can get the front of the range
}));
}

Envisioned (simplified):

template lval(T)
{
  static @property ref T lval() { static T r = T.init; return 
r; }

}

template isInputRange(R)
{
  enum bool isInputRange =
(is(typeof({if(lval!R.empty) {}})
  || pragma(err, "cannot test for empty")) &&
(is(typeof(lval!R.popFront())
  || pragma(err, "cannot invoke popFront")
(is(typeof({ return lval!R.front; }))
  || pragma(err, can get the front of the range));
}

Then the way it goes, the compiler collects the concatenation 
of pragma(msg, "xxx") during the invocation of isInputRange!R 
and prints it if it fails as part of a constraint.


Further simplifications should be possible, e.g. make is() 
support an error string etc.


The problem here is that *every* constraint must be modified, 
which will a long and tedious process. The nice part about 1 is 
that every constraint gets it for free. Applying it recursively 
would provide a nice "stack trace" of constraint failure so the 
user can see exactly what went wrong and where. The problem then 
becomes the verbosity of errors, but we already have ways of 
dealing with that such as the -v switch.

Re: Garbage Collector : Ignoring a reference

[Marco Leise via Digitalmars-d-learn]

Am Tue, 26 Apr 2016 13:35:37 +
schrieb Begah :

> When the screen switches to another screen ie from menu to the 
> game,
> I want that the "button.png" texture is automaticly destroyed by 
> the gc.

My ideological point of view is that you must not use
non-deterministic garbage collection for resources. Neither
for files, GUI widgets or textures. The garbage collector
cannot look past its own confined environment (heap memory
allocated by the D program and loaded D libraries) and will
not have enough information to tell if the process is running
out of file handles, backing buffer for widgets or texture
memory on the graphics card. It only takes action, when its own
heap is filling up or when you manually call GC.collect().
All the convenient 100% GC languages from Java to Python
require the user to call ".close()" for files,
".dispose()/.Destroy()" for widgets, etc.
Reference counting is the correct approach. It makes using
external resources safe and convenient by removing the need
for manual lifetime management. Cyclic references cannot
exist in the D code in this scenario.

The texture constructor:
- sets ref count to 1
- adds texture to hash map
The copy constructor:
- increments the ref count
The destructor:
- decrements the ref count
- if ref count reaches 0:
  - removes the texture from the hash table
  - destroys the texture data

-- 
Marco

Re: Checking if an Integer is an Exact Binary Power

[Xinok via Digitalmars-d]

On Monday, 25 April 2016 at 15:35:14 UTC, Dominikus Dittes 
Scherkl wrote:

On Monday, 25 April 2016 at 15:27:02 UTC, Xinok wrote:

Brute force.

http://dpaste.dzfl.pl/882d7cdc5f74

Yeah. And your test spares the failed case int.min (0x8000),
because in this case x & -x is negative, but of cause x>>>1 is 
positive, so it returns false despite -(2^^31) is in fact a 
power of two. So this requires an extra cast to work correct 
(in fact no big difference in the assembly):


return (Unsigned!T)(x & -x) > (Unsigned!T)(x >>> 1);


How is it wrong? Negative numbers are NOT powers of two (unless 
you have an imaginary/complex exponent), so it's still correct to 
return false for -int.min. Should it not?


http://www.wolframalpha.com/input/?i=solve+2^n+%3D+-%282^31%29+for+n

Re: Live streaming of DConf 2016: confirmed

[Dmitry via Digitalmars-d-announce]

On Tuesday, 26 April 2016 at 14:44:42 UTC, Dicebot wrote:
For high quality recordings publishes later shouldn't be a 
problem.

Very good!

[Issue 15860] lockstep should support foreach_reverse

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=15860

--- Comment #3 from github-bugzi...@puremagic.com ---
Commits pushed to master at https://github.com/dlang/phobos

https://github.com/dlang/phobos/commit/154b0e9cb8f9b0d93a59faf913006a4b66862bc9
Fix Issue 15860 - lockstep should support foreach_reverse

https://github.com/dlang/phobos/commit/23fcb244efbb545485fb5fd8635144340e4193d3
Merge pull request #4138 from Biotronic/fix-15860

Fix Issue 15860 - lockstep should support foreach_reverse

--

[Issue 15860] lockstep should support foreach_reverse

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=15860

github-bugzi...@puremagic.com changed:

   What|Removed |Added

 Status|NEW |RESOLVED
 Resolution|--- |FIXED

--

Re: Live streaming of DConf 2016: confirmed

[Dicebot via Digitalmars-d-announce]

On Tuesday, 26 April 2016 at 14:01:56 UTC, Dmitry wrote:

On Thursday, 21 April 2016 at 17:24:43 UTC, Dicebot wrote:
Have just got a confirmation that there will both live stream 
and high quality recording for later publishing during DConf 
2016 @ Berlin - not being able to attend is not a reason to 
not participate! ;)


Any chance for subtitles?


For live stream - don't think so. For high quality recordings 
publishes later shouldn't be a problem.

Re: Minecraft written in D - on Android

[Benjamin Thaut via Digitalmars-d-announce]

On Tuesday, 26 April 2016 at 08:42:21 UTC, Vadim Lopatin wrote:
Demo of DlangUI Scene3D engine - Minecraft-like voxel rendering 
- is available for Android/ARM.


Post screenshots please.

Re: Checking if an Integer is an Exact Binary Power

[Marco Leise via Digitalmars-d]

Am Mon, 25 Apr 2016 17:04:43 +
schrieb tsbockman :

> On Monday, 25 April 2016 at 16:48:14 UTC, Lass Safin wrote:
> > Example;
> >
> > import core.bitop;
> > import core.cpuid;
> >
> > int count;
> > if(hasPopcnt)
> > count = _popcnt; // Uses x86-instruction "popcnt".
> > else
> > count = popcnt; // Phobos's software implementation.
> >
> > // Do stuff with count  
> 
> That is not right (since 2.069, I think?). Adding that check just 
> makes things slower and more complicated:
> 
> core.bitop.popcnt() itself already checks hasPopcnt, and forwards 
> to the intrinsic if it is available.

Can we just use __traits(hasTargetFeature, "popcnt") already
and get rid of _popcnt?

-- 
Marco

Compare lambda expressions

[Alex via Digitalmars-d-learn]

Hi all!

Not sure, if this belongs directly to the D language, or it is 
rather maths, but:

given to delegate generating functions and a main

auto func1(int arg)
{
bool delegate(int x) dg;
dg = (x) => arg * x;
return dg;
}

auto func2(int arg)
{
bool delegate(int x) dg;
dg = (x) => arg * x * x / x;
return dg;
}

void main()
{
auto dgf1 = func1(4);
writeln(dgf1(2));
auto dgf2 = func2(4);
writeln(dgf2(2));
writeln(dgf1 == dgf2);
}

the last line gives false, either in this form, as well with 
.ptr, as well with .funcptr.


The question is, how to say, whether two lambda expressions are 
the same?
What if the lambda expressions are predicates? This case would be 
more important for me...


I understand, that there is only a little hope to get answer 
other then "impossible", even for the constrained case. In such a 
case, I have another opportunity:


Say, I define two lambda functions as strings in, say a json 
file. I'm going to parse them and build functions out of them.
How to force the input in a unified manner? In such a case, I 
could compare the given strings with some weird regular 
expression...

So, the question for this case is:
Is there some normalized form of writing a lambda expression? Any 
literature would be more then sufficient as an answer...


Many thanks in advance :)

Re: So, to print or not to print?

[tn via Digitalmars-d]

On Tuesday, 26 April 2016 at 12:52:13 UTC, Andrei Alexandrescu 
wrote:

On 04/26/2016 08:18 AM, cym13 wrote:
The first questions I expect are "when should I use print and 
when use

writeln?" for they share a common role with common features.


"When you want spaces between arguments and when you don't".

We've been over this. Nobody asks when they should use writef 
over writeln or readf over readln (which also share a common 
role with common features).


Maybe the name of the function should then be "writes" and/or 
"writesln" (instead of "print"), so that it can at least be found 
from the same place in the documentation as other related 
functions. The naming scheme would then also be consistent with 
the rest of the write/writef-family. (Here -s stands for 
"separated/spaced" just as -f stands for "formatted" etc.)

Re: Minecraft written in D - on Android

[WebFreak001 via Digitalmars-d-announce]

On Tuesday, 26 April 2016 at 08:42:21 UTC, Vadim Lopatin wrote:

Hello,


Demo of DlangUI Scene3D engine - Minecraft-like voxel rendering 
- is available for Android/ARM.


Download DlangUIMinecraftDemo.apk from 
https://sourceforge.net/projects/crengine/files/DlangUI/


Image is a bit corrupted with some artifacts.

On desktop it works better: `dub run dlangui:dminer`

Another demo of DlangUI 3d engine: `dub run dlangui:d3d`

DlangUI/Scene3d is simple 3D engine. Supports, cameras, lights, 
meshes, hierarchy of nodes, transforms, models, meshes, 
materials, shaders. For now, only OBJ 3d model import is 
implemented. No physics engine integrated so far.



Best regards,
Vadim


On my android device it says "Failed to parse package"

Also where is the source at so I can run dub manually?

Re: So, to print or not to print?

[cym13 via Digitalmars-d]

On Tuesday, 26 April 2016 at 12:52:13 UTC, Andrei Alexandrescu 
wrote:

On 04/26/2016 08:18 AM, cym13 wrote:
The first questions I expect are "when should I use print and 
when use

writeln?" for they share a common role with common features.


"When you want spaces between arguments and when you don't".

We've been over this. Nobody asks when they should use writef 
over writeln or readf over readln (which also share a common 
role with common features). What precedent do you have of 
people getting confused like that?



Andrei


Well, just the post above your own there's a case of someone who 
didn't expect the separation. I think it makes my point.

Re: So, to print or not to print?

[Adam D. Ruppe via Digitalmars-d]

On Tuesday, 26 April 2016 at 12:52:13 UTC, Andrei Alexandrescu 
wrote:

"When you want spaces between arguments and when you don't".


As I have said before, other languages have tried this kind of 
thing... and they aren't remembered well for it.


substr vs substring in javascript is the first big example. 
Similar name, subtle difference.

Re: Some questions on latest work

[ag0aep6g via Digitalmars-d]

On 26.04.2016 10:20, Suliman wrote:

Do you really think that modern language should like this?

I talked with a lot of rust fun-boys. Most of them do not understand do
not understand the code of their favourite language.

Rust will die when Mozilla will move to WebKit. I much more believe in
Swift success, that that Rust have any future.


Please don't bash on other languages, especially when they're perceived 
as competition. It reflects badly on the D community.

Re: So, to print or not to print?

[cym13 via Digitalmars-d]

On Tuesday, 26 April 2016 at 12:46:09 UTC, Andrei Alexandrescu 
wrote:

On 04/26/2016 04:50 AM, ixid wrote:
Please find an example of a newcomer who would be confused by 
print.
This is an objectionable argument because none of the people 
making it
are newcomers, you're using an entirely theoretical newcomer 
as your
argument, and seem to think 'print(a, b, c);' is going to 
confuse people

more than 'writefln("%s %s %s", a, b, c);' which is ridiculous.


Let me also add that the very request came from a former 
newcomer. -- Andrei


Well except maybe for you and Walter I think we're all former 
newcomers.

Re: Garbage Collector : Ignoring a reference

[ciechowoj via Digitalmars-d-learn]

Thus, i need a way to tell the gc to ignore the reference ( or 
something similar ) in that hashmap.


So, having pointer that doesn't hold a reference isn't that hard 
(store it in memory region that is unreachable to gc), but don't 
you need a way to tell if that pointer ins't dangling, beyond 
initial problem?

Re: So, to print or not to print?

[Adam D. Ruppe via Digitalmars-d]

On Tuesday, 26 April 2016 at 12:46:48 UTC, Seb wrote:
the separation between std.stdio and std.file. At least I 
expected that I can use `writeln` on files :/


You can...

auto file = File("name.txt", "wt");
file.writeln("hey");

As mentioned on github I would love to see a proper dump 
function and this would be quite useful for newcomers.


Yeah, dump has serious value, I'd support it.

Re: Some questions on latest work

[Adam D. Ruppe via Digitalmars-d]

On Tuesday, 26 April 2016 at 04:37:03 UTC, deadalnix wrote:

On 32 bits, nothing fundamental changed, but the compiler
got a bit smarter about alocating with the no scan flag,
so that's better.


Indeed, though any large array is liable to be pinned by a false 
pointer on 32 bit, even with no_scan.


I actually recommend malloc/free large arrays with easy lifetimes 
on 32 bit just to avoid those accidental leaks.


64 bit is fine though.

I don't know for that one, but if that doesn't work with 
classes, this is indeed a problem worth solving.


I think it kinda works now but not very well because the ref 
countedness gets lost in inheritance. If it implements two 
interfaces for example, it cannot properly express that implicit 
conversion.


Usable though AFAIK, just clunky.

[Issue 15958] Missing extern(Windows) of core.sys.windows functions

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=15958

j...@red.email.ne.jp changed:

   What|Removed |Added

   Keywords||pull

--- Comment #1 from j...@red.email.ne.jp ---
https://github.com/dlang/druntime/pull/1550

--

Re: Garbage Collector : Ignoring a reference

[ag0aep6g via Digitalmars-d-learn]

On 26.04.2016 15:35, Begah wrote:

Nothing will reload.

An example :
I load a texture "button.png" in a class and draw it to the screen,
When the screen switches to another screen ie from menu to the game,
I want that the "button.png" texture is automaticly destroyed by the gc.
But this will never happen because i still have a reference to it in my
hashmap.
Thus, i need a way to tell the gc to ignore the reference ( or something
similar ) in that hashmap.


How would you prevent reads of that now-invalid element of the hashmap?

Re: Garbage Collector : Ignoring a reference

[Begah via Digitalmars-d-learn]

On Tuesday, 26 April 2016 at 13:01:26 UTC, ciechowoj wrote:

On Tuesday, 26 April 2016 at 09:07:59 UTC, Begah wrote:
How could i tell the garbage collector to ignore the reference 
in the hashmap and to free it if there isn't any other 
reference that in my hashmap?


You could always zero the reference in the hashmap, as it won't 
be valid after reload anyway...


Nothing will reload.

An example :
I load a texture "button.png" in a class and draw it to the 
screen,
When the screen switches to another screen ie from menu to the 
game,
I want that the "button.png" texture is automaticly destroyed by 
the gc.
But this will never happen because i still have a reference to it 
in my hashmap.
Thus, i need a way to tell the gc to ignore the reference ( or 
something similar ) in that hashmap.

Re: Changelog entries as folder or in wiki

[ag0aep6g via Digitalmars-d]

On 21.04.2016 01:51, Seb wrote:

It would be great if we had a better, painless way to handle the
changelog - two simple ideas:

1) Use a changelog folder instead of file


After having rebased a pull request for the third time just because of 
changelog.dd: Sounds good to me.

Re: Checking if an Integer is an Exact Binary Power

[Matthias Bentrup via Digitalmars-d]

On Tuesday, 26 April 2016 at 08:12:02 UTC, Dominikus Dittes 
Scherkl wrote:

On Monday, 25 April 2016 at 22:42:38 UTC, deadalnix wrote:
x & -x is the smallest power of 2 that divides x. Basically, 
if x = 1000 , x & -x = 1000 . This is easy to proves 
considering -x = ~x + 1 .


Now, x >> 1 will be of the form 0100 . If one of these 
digit is one, then (x >> 1) >= (x & -x) . If they are all 
zeros, (x >> 1) < (x & -x) which is the case where you have a 
power of 2.


0 is a special case, can it can be checked that the function 
return false for this specific input.


This looks like it is correct.


Yes. Except for the case 0x8000 (= int.min), because this 
is negative so NOT smaller than 0x4000 (= int.min>>>1), 
which is considered positive.
So the algorithm doesn't work for signed integers (without 
extra cast).


Well, it depends a bit on how you define "is a power of two":

 If you define "x is a power of 2" as "there is a natural number 
n, so that x == 2*2*...*2 (n-times)" with * defined as 
multiplication in the ring of integers modulo 2^32 (i.e. int or 
uint), then int.min and 0 are powers of two because the 
multiplication overflows.


 If you define "x is a power of 2" as above but based on the 
multiplication in the ring of integers, then int.min (== -2^31) 
and 0 are not powers of two.

Re: So, to print or not to print?

[Andrei Alexandrescu via Digitalmars-d]

On 04/26/2016 08:46 AM, Seb wrote:

I can out myself as a newcomer (since February) and a lot of stuff in D
is pretty confusing. For example - a bit related - the separation
between std.stdio and std.file. At least I expected that I can use
`writeln` on files :/


Thanks for your insight! Could someone insert an explanation at the top 
of both std.file and std.stdio, built from the following point:


Artifacts in std.stdio treat files as complex data repositories that are 
opened, read from and/or written to, and closed. Artifacts in std.file 
treat a file as a unit, much like shell programs do. With std.file 
read/write operations are done at the level of the entire file at once, 
and details of opening and closing are implicit.



Honestly, I see no value whatsoever in print. writefln already does
the same job and in a clearer manner.


Or `writeln(chain(a, b, c).join(','))`.


That's just a terrible argument, sorry. The whole point here is to not 
necessitate introducing too many language and library artifacts in order 
to print something.



Andrei

Re: Simple and effective approaches to constraint error messages

[Atila Neves via Digitalmars-d]

On Monday, 25 April 2016 at 17:52:58 UTC, Andrei Alexandrescu 
wrote:
It's been long asked in our community that failing template 
constraints issue better error messages. Consider:


[...]


I still prefer static inheritance. Having said that, I like the 
pragma(err) thing in the template constraint.


Atila

Re: Garbage Collector : Ignoring a reference

[ciechowoj via Digitalmars-d-learn]

On Tuesday, 26 April 2016 at 09:07:59 UTC, Begah wrote:
How could i tell the garbage collector to ignore the reference 
in the hashmap and to free it if there isn't any other 
reference that in my hashmap?


You could always zero the reference in the hashmap, as it won't 
be valid after reload anyway...