rpc between Tasks of vibe.d

[crimaniak via Digitalmars-d-learn]

Hi All!

I will try to illustrate by code what exactly I have in mind:

// we have not shared class/struct with some interface.
class FooController
{
...
int foo1(int a, string b);
string foo2(Struct1 c);
...
}

// now we want to make a running task with an instance inside

auto controllerTask = runTask((){

  auto controller = new FooController();
  ReceiveCalls!FooController(controller);

});


// and call it from other tasks, like this

int result1 = Call!FooController(controllerTask).foo1(123, "abc");
string result2 = 
Call!FooController(controllerTask).foo2(Struct1(...));



Is there any interface generator for this? Or what can you 
suggest?


Thanks!

[Issue 16645] 3 errors messages instead of 1 after CTFE divide by 0

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=16645

b2.t...@gmx.com changed:

   What|Removed |Added

   Keywords||CTFE

--

[Issue 16645] New: 3 errors messages instead of 1 after CTFE divide by 0

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=16645

  Issue ID: 16645
   Summary: 3 errors messages instead of 1 after CTFE divide by 0
   Product: D
   Version: D2
  Hardware: All
OS: All
Status: NEW
  Severity: minor
  Priority: P1
 Component: dmd
  Assignee: nob...@puremagic.com
  Reporter: b2.t...@gmx.com

echo "enum a = 0/0;" > d.d && dmd d.d -main

prints:

> d.d(1): Error: divide by 0
> d.d(1): Error: divide by 0
> d.d(1): Error: divide by 0

--

Re: Mir GLAS is a C library and passes Natlib's test suite! And questions :-)

[Nicholas Wilson via Digitalmars-d]

On Friday, 28 October 2016 at 16:14:56 UTC, Sameer Pradhan wrote:


I must plead ignorance on the finer interface details, but from 
what I am reading this seems like an amazing development. I am 
so happy that that D has a solid base for GPU work.


The post from a few weeks back with performance details 
compared to BLAS and others was quite impressive. details I was 
just telling Steve at the Boston meetup yesterday that libmir 
and now MirGLAS has really made me jump up and down to start 
using D seriously for some language processing work I have been 
hoping to use it for. I have been an observer and reader for 
several years now, but haven't taken the leap. Yet. Hopefully 
soon...


--
Sameer



For GPUs there is dcompute (also on libmir's github) on the way, 
although it'll be probably another month (exams, joy!) before the 
compiler stuff gets fully merged into LDC and we can start on an 
API that forwards to OpenCL/CUDA, and doesn't suck to use.


If you have any experience with either OpenCL or CUDA we'd love 
to have your input.

[Issue 16644] New: final switch on int should error unless VRP matches all cases

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=16644

  Issue ID: 16644
   Summary: final switch on int should error unless VRP matches
all cases
   Product: D
   Version: D2
  Hardware: All
OS: All
Status: NEW
  Severity: normal
  Priority: P1
 Component: dmd
  Assignee: nob...@puremagic.com
  Reporter: c...@dawg.eu

To determine whether all cases are handled, we could use value range
propagation.

OK

final switch (i % 2)
{
case 0:
case 1:
}

ERROR
final switch (i % 3)
{
case 0:
case 1:
}

In cases where we don't know the range, it should be an error.

--

Re: D garbage collector and real-time systems

[Yuxuan Shui via Digitalmars-d]

On Wednesday, 28 January 2015 at 07:43:35 UTC, ketmar wrote:

On Wed, 28 Jan 2015 06:58:41 +, Tom wrote:

Or is there now the possibility of disabling the GC 
altogether, or replacing it with a refcounting 'GC' etc?


you still can do manual memory management with `malloc()` and 
friends. but you must be very cautious with dynamic arrays and 
slices. may be your best bet is to not use built-in dynamic 
arrays at all and write a replacement class with manual memory 
management. ah, and the same for AAs.


it's possible, if somewhat cumbersome. and you can use 'dmd 
-vgc' to check for hidden allocations. so it may be not as 
simple as adding some compiler switch, but still not that hard 
too.


For manually managed arrays, containers, I would recommend the 
emsicontainers (https://github.com/economicmodeling/containers)

Re: Is there Typeof template ?

[Temtaime via Digitalmars-d-learn]

On Friday, 28 October 2016 at 18:39:36 UTC, Ali Çehreli wrote:
On 10/28/2016 11:25 AM, Jonathan M Davis via 
Digitalmars-d-learn wrote:


>> void main() {
>>  @(`str`, 123) uint k;
>>  foreach (a; __traits(getAttributes, k)) {
>>  pragma(msg, typeof(a));
>>  }
>> }

> I don't know if Typeof is actually needed for what the OP is
trying to do,
> but if you wanted to apply typeof using something like
std.meta.staticMap,
> then you'd need something like Typeof.

I see.

Just to add something that I've just remembered, it is possible 
to apply typeof to __traits(getAttributes) as well:


foreach (T; typeof(__traits(getAttributes, k))) {
pragma(msg, T);
}

Now we get a list of types:

string
int

Ali


I wanna use it with staticMap.

Re: Binding temporaries to ref [WAS: I close BIP27. I won't be pursuing BIPs anymore]

[bitwise via Digitalmars-d]

On Friday, 21 October 2016 at 07:56:40 UTC, Ethan Watson wrote:
On Thursday, 20 October 2016 at 19:49:42 UTC, Andrei 
Alexandrescu wrote:
I think a solid DIP addressing the problem would have a good 
chance to get traction.


I think all the information in this thread and the "Binding 
rvalues to const ref in D" thread that Atilla started is enough 
for me to write up a solid DIP.


I'll start doing that. Hopefully I'll get a draft up that I'll 
pass to Manu for comment/input this weekend before posting it 
properly.


Any news on this?

[Issue 16643] CTFE internal error with null

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=16643

ag0ae...@gmail.com changed:

   What|Removed |Added

   Keywords||ice
 CC||ag0ae...@gmail.com

--

Re: Is there Typeof template ?

[Ali Çehreli via Digitalmars-d-learn]

On 10/28/2016 11:25 AM, Jonathan M Davis via Digitalmars-d-learn wrote:

>> void main() {
>>  @(`str`, 123) uint k;
>>  foreach (a; __traits(getAttributes, k)) {
>>  pragma(msg, typeof(a));
>>  }
>> }

> I don't know if Typeof is actually needed for what the OP is trying 
to do,
> but if you wanted to apply typeof using something like 
std.meta.staticMap,

> then you'd need something like Typeof.

I see.

Just to add something that I've just remembered, it is possible to apply 
typeof to __traits(getAttributes) as well:


foreach (T; typeof(__traits(getAttributes, k))) {
pragma(msg, T);
}

Now we get a list of types:

string
int

Ali

Re: Is there Typeof template ?

[Jonathan M Davis via Digitalmars-d-learn]

On Friday, October 28, 2016 11:19:46 Ali Çehreli via Digitalmars-d-learn 
wrote:
> On 10/28/2016 05:48 AM, Temtaime wrote:
> > On Friday, 28 October 2016 at 12:44:20 UTC, Adam D. Ruppe wrote:
> >> On Friday, 28 October 2016 at 10:52:05 UTC, Temtaime wrote:
> >>> Are there something or should I create a PR to phobos?
> >>
> >> Why would you want that?
> >
> > I have UDAs with values à la @(`str`, 123) uint k;
> >
> > And i want to know a type of a value.
>
> How are you using those? typeof works with any value:
>
> void main() {
>  @(`str`, 123) uint k;
>  foreach (a; __traits(getAttributes, k)) {
>  pragma(msg, typeof(a));
>  }
> }
>
> Prints
>
> string
> int
>
> You can use indexes with the loop as well:
>
>  foreach (i, a; /* ... */

I don't know if Typeof is actually needed for what the OP is trying to do,
but if you wanted to apply typeof using something like std.meta.staticMap,
then you'd need something like Typeof.

- Jonathan M Davis

Re: Fun: Shooting yourself in the foot in D

[Ali Çehreli via Digitalmars-d]

On 10/28/2016 04:41 AM, John Colvin wrote:

> a bullet that's paused by the GC

Wow. I've just said almost the same thing before reading this one. :)

Ali

Re: Fun: Shooting yourself in the foot in D

[Ali Çehreli via Digitalmars-d]

On 10/28/2016 04:32 AM, Guillaume Piolat wrote:

> When you try shooting at your foot with your AK-47, you realize the GC
> has blown it already.

Or... the bullet stops midair, waiting for the GC to finish a collection 
cycle (probably for a lollipop created in another thread).


Ali

Re: Is there Typeof template ?

[Ali Çehreli via Digitalmars-d-learn]

On 10/28/2016 05:48 AM, Temtaime wrote:

On Friday, 28 October 2016 at 12:44:20 UTC, Adam D. Ruppe wrote:

On Friday, 28 October 2016 at 10:52:05 UTC, Temtaime wrote:

Are there something or should I create a PR to phobos?


Why would you want that?


I have UDAs with values à la @(`str`, 123) uint k;

And i want to know a type of a value.


How are you using those? typeof works with any value:

void main() {
@(`str`, 123) uint k;
foreach (a; __traits(getAttributes, k)) {
pragma(msg, typeof(a));
}
}

Prints

string
int

You can use indexes with the loop as well:

foreach (i, a; /* ... */

Ali

Re: CTFE divide by 0 prints the same error 3 times !

[Ali Çehreli via Digitalmars-d-learn]

On 10/28/2016 07:37 AM, Basile B. wrote:

try this

echo "enum a = 0/0;" > d.d && dmd d.d -main

any reason for this ?


One is too easy to miss, two is better, but three is just right. :o)

Must be an implementation oddity. Please file a bug.

Ali

Re: A question of function design?

[WhatMeWorry via Digitalmars-d-learn]

On Friday, 28 October 2016 at 14:12:53 UTC, Mike Parker wrote:

On Friday, 28 October 2016 at 13:19:19 UTC, WhatMeWorry wrote:


[...]


I generally use GLFW event callbacks to populate an event queue 
with custom event types, then process the queue and handle 
events elsewhere. That way, the callbacks need no nothing at 
all about the game code.


[...]


Thanks!  I'll study this code.  I guess APIs can only give you so 
much.

Re: Battle-plan for CTFE

[Stefan Koch via Digitalmars-d-announce]

Another update on CTFE.

I have found a few errors in my handling of switch-statments.
An efficient solution for this is still pending,

Futhermore I have begun to work on ctfe handling refernces.
These are a little bit harder to do in bytecode and do pessimise 
performance if overused.


I hope to make another leap at the end of this month.

We should have string Concat-support fairly soon.

Cheers,
stefan

DLang Youtube channel

[Patric Dexheimer via Digitalmars-d]

There isn't a official D youtube channel right?
Would be  be nice to have all the D related videos spread on 
youtube centralized in one place :)

Re: Mir GLAS is a C library and passes Natlib's test suite! And questions :-)

[Sameer Pradhan via Digitalmars-d]

On Friday, 28 October 2016 at 06:31:19 UTC, Ilya Yaroshenko wrote:
On Friday, 28 October 2016 at 03:44:05 UTC, Andrei Alexandrescu 
wrote:

On 10/27/16 3:59 AM, Ilya Yaroshenko wrote:

[...]


I must plead ignorance on the finer interface details, but from 
what I am reading this seems like an amazing development. I am so 
happy that that D has a solid base for GPU work.


The post from a few weeks back with performance details compared 
to BLAS and others was quite impressive. details I was just 
telling Steve at the Boston meetup yesterday that libmir and now 
MirGLAS has really made me jump up and down to start using D 
seriously for some language processing work I have been hoping to 
use it for. I have been an observer and reader for several years 
now, but haven't taken the leap. Yet. Hopefully soon...


--
Sameer




[...]


Cool work!

One thing I'd want to understand is how to use Mir GLAS from 
within D itself. If it's a straight C interface, there seems 
to be a fair amount of friction (we have a D program 
communicating with a D library through the uncomfortable 
confines of a C interface). Is that the case? Should there be 
a way to short circuit the C API and use a more expressive D 
interface? (Looking e.g. at Eigen, it's meant to allow people 
using it from C++ to take advantage of a C++-specific smooth 
interface.)


GLAS has 2 APIs: GLAS(ndslise) and BLAS(fortran).
Both APIs has C/C++ and D headers. D headers contains aliases 
with unified names like in core.stdc.tgmath. So, extern(C) 
interface for GLAS is comfortable and looks like:


gemm(alpha, a, b, beta, c); // calls glas_?gemm

The latest ndslice PR to stable branch solves a problem in case 
of const and immutable a and b. 
https://github.com/dlang/phobos/pull/4873


GLAS does not have syntax like Eigen, i mean

c = a * b;

This syntax can be a part of another package for scripting like 
syntax.
See also Q 
https://github.com/libmir/mir-glas#why-glas-does-not-have-lazy-evaluation-and-aliasing-like-eigen



[...]


I guess I'd like to understand the dynamics better here.


The main reason is compilation time (1 secs+) and template 
bloat (50 KB +). OpenBLAS size is more than 20 MB. GLAS is 
smaller, but it is not something lightweight like `sort`.
Assume you are buildings a large D projects one-by-one file in 
parallel. It can be builded during minutes and its size can be

>100 MB, only because GLAS.

So, having an extern(C) layers is good practice to keep 
interface clear and compile time small.



[...]


You have all support from Walter and myself for integrating 
GLAS with Phobos. Before that I'd want to make sure we slice 
and dice things properly.


Awesome! I am happy to read this)


[...]


That would be an interesting precedent. We should talk about 
it next week. (My knee-jerk reaction is if we're worth our 
salt we should release Phobos often enough to obviate the need 
for this. But the notion of hot-swapping subcomponents is cool 
too.)


Some concepts can be found on a slides from my today's talk
https://docs.google.com/presentation/d/1w1cQ8vDluglRIt8Qdnm-sY7kqxoKZxbPEWW6tR3lPpo/edit?usp=sharing


Thanks,

Andrei


Best regards,
Ilya

Re: Pattern matching in D?

[Dennis Ritchie via Digitalmars-d]

Someone may be, it will be interesting, in the C# 7 `switch` will 
be extended syntax for pattern matching:

https://github.com/dotnet/roslyn/blob/features/patterns/docs/features/patterns.md

Original post:
https://github.com/dotnet/roslyn/issues/206

Re: Best approach to handle accented letters

[Alfred Newman via Digitalmars-d-learn]

On Friday, 28 October 2016 at 15:08:59 UTC, Chris wrote:

On Friday, 28 October 2016 at 14:31:47 UTC, Chris wrote:

[...]


What you basically do is you pass the logic on to `map` and 
`map` applies it to each item in the range (cf. [1]):


[...]


The life is beautiful !
Thx.

Re: Is there a D static site generator based on markdown (like couscous) ?

[Guillaume Piolat via Digitalmars-d-learn]

On Friday, 28 October 2016 at 13:37:55 UTC, Basile B. wrote:
I would need actually something like 
https://github.com/CouscousPHP/Couscous but in D.


You can easily make a custom SSG with 
https://github.com/kiith-sa/dmarkdown

Re: Best approach to handle accented letters

[Chris via Digitalmars-d-learn]

On Friday, 28 October 2016 at 14:31:47 UTC, Chris wrote:

On Friday, 28 October 2016 at 13:50:24 UTC, Alfred Newman wrote:

It boils down to something like:

if (c in _accent)
  return _accent[c];
else
  return c;

Just a normal lambda (condition true) ? yes : no;

I'd recommend you to use Marc's approach, though.


What you basically do is you pass the logic on to `map` and `map` 
applies it to each item in the range (cf. [1]):


map!(myLogic)(range);

or (more idiomatic)

range.map!(myLogic);

This is true of a lot of functions, or rather templates, in the 
Phobos standard library, especially functions in std.algorithm 
(like find [2], canFind, filter etc.). In this way, instead of 
writing for-loops with if-else statements, you pass the logic to 
be applied within the `!()`-part of the template.


// Filter the letter 'l'
auto result = "Hello, world!".filter!(a => a != 'l'); // returns 
"Heo, word!"


However, what is returned is not a string. So this won't work:

`writeln("Result is " ~ result);`

// Error: incompatible types for (("Result is ") ~ (result)): 
'string' and

// 'FilterResult!(__lambda2, string)'

It returns a `FilterResult`.

To fix this, you can either write:
`
import std.conv;
auto result = "Hello, world!".filter!(a => a != 'l').to!string;
`
which converts it into a string.

or you do this:

`
import std.array;
auto result = "Hello, world!".filter!(a => a != 'l').array;
`

Then you have a string again and

`
writeln("Result is " ~ result);
`
works.

Just bear that in mind, because you will get the above error 
sometimes. Marc's example is idiomatic D and you should become 
familiar with it asap.


void main()
{
auto str = "très élégant";
immutable accents = unicode.Diacritic;
auto removed = str
// normalize each character
.normalize!NFD
// replace each diacritic with its non-diacritic 
counterpart

.filter!(c => !accents[c])
// convert each item in FilterResult back to string.
.to!string;
writeln(removed);  // prints "tres elegant"
}

[1] http://dlang.org/phobos/std_algorithm_iteration.html#.map
[1] http://dlang.org/phobos/std_algorithm_searching.html#.find

Re: Avoiding GC

[Guillaume Piolat via Digitalmars-d-learn]

On Friday, 28 October 2016 at 11:50:20 UTC, hardreset wrote:
On Thursday, 27 October 2016 at 07:52:09 UTC, Guillaume Piolat 
wrote:

On Wednesday, 26 October 2016 at 08:18:07 UTC, hardreset wrote:
Is there a page somewhere on how to program D without using 
the GC?


The information is scattered.


How do I allocate / free structs / classes on the heap 
manually?


Classes => 
https://github.com/AuburnSounds/dplug/blob/master/core/dplug/core/nogc.d#L122


Thanks.

I notice you avoid GC altogether in dplug. Whats the reason for 
total avoidance as apposed to just avoiding it in the real time 
code?


Not a lot of reason.
It's very recent work, I'm still struggling making threadpool 
works.


- Reason #1 was that it gives a way to unload shared libraries on 
OSX. This bug has been fixed in LDC but would require to make 
druntime and phobos a shared library to ship. That makes releases 
3x larger so I went with disabling the runtime instead (one month 
of work and still going...).


- Reason #2 is that GC does use more memory. Next release of our 
products use 2x fewer memory.


All in all it's _painful_ not to use the D runtime, suddenly you 
can't use third-party code, and there is no performance 
enhancement to expect apart from reduced memory usage.


Don't avoid the runtime on principles alone.

[Issue 16643] New: CTFE internal error with null

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=16643

  Issue ID: 16643
   Summary: CTFE internal error with null
   Product: D
   Version: D2
  Hardware: All
OS: All
Status: NEW
  Severity: minor
  Priority: P1
 Component: dmd
  Assignee: nob...@puremagic.com
  Reporter: b2.t...@gmx.com

null+null and null-null trigger the error:

echo "enum a = null+null;" > d.d && dmd d.d -main
echo "enum a = null-null;" > d.d && dmd d.d -main

> Error: CTFE internal error: non-constant value null

--

CTFE divide by 0 prints the same error 3 times !

[Basile B. via Digitalmars-d-learn]

try this

echo "enum a = 0/0;" > d.d && dmd d.d -main

any reason for this ?

Re: Best approach to handle accented letters

[Chris via Digitalmars-d-learn]

On Friday, 28 October 2016 at 13:50:24 UTC, Alfred Newman wrote:

On Friday, 28 October 2016 at 11:40:37 UTC, Chris wrote:

[...]


@Chris

As a new guy in the D community, I am not sure, but I think the 
line below is something like a Python's lambda, right ?


auto removed = to!string(str.map!(a => (a in _accent) ? 
_accent[a] : a));


Can you please rewrite the line in a more didatic way ? Sorry, 
but I'm still learning the basics.


Thanks in advance


It boils down to something like:

if (c in _accent)
  return _accent[c];
else
  return c;

Just a normal lambda (condition true) ? yes : no;

I'd recommend you to use Marc's approach, though.

Re: The DLang UPB Languages and Systems Research Scholarship

[Mike Parker via Digitalmars-d-announce]

On Friday, 28 October 2016 at 13:57:37 UTC, Mike Parker wrote:


How is a scholarship for CS degrees off topic?


OK, nevermind. Been a while since I looked at the sidebar.


"If there is no code in your link, it probably doesn't belong 
here."

Re: A question of function design?

[Mike Parker via Digitalmars-d-learn]

On Friday, 28 October 2016 at 13:19:19 UTC, WhatMeWorry wrote:



Anyone have a good example of what I should be doing?


I generally use GLFW event callbacks to populate an event queue 
with custom event types, then process the queue and handle events 
elsewhere. That way, the callbacks need no nothing at all about 
the game code.


```
void setCallbacks() {
glfwSetKeyCallback(_callback);
}

private:
MyEventQueue _eventq;

extern(C) void key_callback(GLFWwindow* window, int key, int 
scancode, int action, int modifier) {

eventq.push(KeyEvent(window, key, scancode, action, modifier);
}

An alternative approach is to forego the event queue and just 
have the callbacks process event listeners. The listeners could 
be delegates, function pointers, or interfaces, whatever works 
for your scenario, or some specific event handler class. They 
might be stored in flat arrays, or aas keyed on the window or a 
KeyEvent structure. Whatever works.


```
alias KeyHandler = bool delegate(GLFWwindow, int, int, int, int);
void registerKeyHandler(KeyHandler handler) { _keyHandlers ~= 
handler; }


private:
KeyHandler[] _keyHandlers;

extern(C) void key_callback(GLFWwindow* window, int key, int 
scancode, int action, int modifier) {

foreach(handler; _keyHandlers) {
if(_keyHandler(window, key, scancode, action, modifier)) 
break;

}
}
```

Re: The DLang UPB Languages and Systems Research Scholarship

[Mike Parker via Digitalmars-d-announce]

On Friday, 28 October 2016 at 10:43:36 UTC, thedeemon wrote:
On Wednesday, 26 October 2016 at 01:11:05 UTC, Mike Parker 
wrote:


For anyone tempted to share this on /r/programming, please 
wait! I hope to do a blog post about this on Friday, so I'll 
post to reddit then. Thanks!


Please don't. This is a total offtopic for /r/programming, 
don't create the reputation "dlang seeks for attention and 
spams with irrelevant stuff".


How is a scholarship for CS degrees off topic?

Re: Best approach to handle accented letters

[Alfred Newman via Digitalmars-d-learn]

On Friday, 28 October 2016 at 11:40:37 UTC, Chris wrote:

On Friday, 28 October 2016 at 11:24:28 UTC, Alfred Newman wrote:

Hello,

I'm getting some troubles to replace the accented letters in a 
given string with their unaccented counterparts.


Let's say I have the following input string "très élégant" and 
I need to create a function to return just "tres elegant". 
Considering we need to take care about unicode chars, what is 
the best way to write a D code to handle that ?


Cheers


You could try something like this. It works for accents. I 
haven't tested it on other characters yet.


import std.stdio;
import std.algorithm;
import std.array;
import std.conv;

enum
{
  dchar[dchar] _accent = ['á':'a', 'é':'e', 'è':'e', 'í':'i', 
'ó':'o', 'ú':'u', 'Á':'A', 'É':'E', 'Í':'I', 'Ó':'O', 'Ú':'U']

}

void main()
{
  auto str = "très élégant";
  auto removed = to!string(str.map!(a => (a in _accent) ? 
_accent[a] : a));

  writeln(removed);  // prints "tres elegant"
}


@Chris

As a new guy in the D community, I am not sure, but I think the 
line below is something like a Python's lambda, right ?


auto removed = to!string(str.map!(a => (a in _accent) ? 
_accent[a] : a));


Can you please rewrite the line in a more didatic way ? Sorry, 
but I'm still learning the basics.


Thanks in advance

Is there a D static site generator based on markdown (like couscous) ?

[Basile B. via Digitalmars-d-learn]

I would need actually something like 
https://github.com/CouscousPHP/Couscous but in D.

Re: Fun: Shooting yourself in the foot in D

[Dominikus Dittes Scherkl via Digitalmars-d]

On Friday, 28 October 2016 at 11:41:11 UTC, John Colvin wrote:
You unregister your feet from the runtime in order to move 
smoothly, wander in front of a bullet that's paused by the GC, 
which then un-pauses and hits you in the foot.


This is the best one so far! This is typical D: circumvent safety 
to enable you to shoot yourself in the foot.

Re: A question of function design?

[WhatMeWorry via Digitalmars-d-learn]

On Thursday, 27 October 2016 at 22:51:13 UTC, pineapple wrote:

On Thursday, 27 October 2016 at 22:17:35 UTC, WhatMeWorry wrote:


I'm using Derelict GLFW3 and I found the following GLFW3 code 
snippet in a demo.


In a small demo, crap like this usually isn't a big deal.

It's not common practice, though, and for good reason. You 
should definitely avoid imitating it.


Anyone have a good example of what I should be doing?

Re: Best approach to handle accented letters

[Chris via Digitalmars-d-learn]

On Friday, 28 October 2016 at 12:52:04 UTC, Marc Schütz wrote:

On Friday, 28 October 2016 at 11:24:28 UTC, Alfred Newman wrote:

[...]


import std.stdio;
import std.algorithm;
import std.uni;
import std.conv;

void main()
{
auto str = "très élégant";
immutable accents = unicode.Diacritic;
auto removed = str
.normalize!NFD
.filter!(c => !accents[c])
.to!string;
writeln(removed);  // prints "tres elegant"
}

This first decomposes all characters into base and diacritic, 
and then removes the latter.


Cool. That looks pretty neat and it should cover all cases.

[Issue 15604] [REG2.070] std.array.array of structs with template opAssign and default initialised 'new'ed class member

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=15604

Martin Krejcirik  changed:

   What|Removed |Added

Summary|std.array.array of structs  |[REG2.070] std.array.array
   |with template opAssign and  |of structs with template
   |default initialised 'new'ed |opAssign and default
   |class member|initialised 'new'ed class
   ||member

--

Re: Is there Typeof template ?

[Jonathan M Davis via Digitalmars-d-learn]

On Friday, October 28, 2016 10:52:05 Temtaime via Digitalmars-d-learn wrote:
> Hi !
> Tried to find
> alias Typeof(alias A) = typeof(A);
> or something, but failed.
>
> Are there something or should I create a PR to phobos?
> Thanks

If it were in Phobos, I'd expect it to be in std.meta, and it's not there.

- Jonathan M Davis

Re: Best approach to handle accented letters

[Marc Schütz via Digitalmars-d-learn]

On Friday, 28 October 2016 at 11:24:28 UTC, Alfred Newman wrote:

Hello,

I'm getting some troubles to replace the accented letters in a 
given string with their unaccented counterparts.


Let's say I have the following input string "très élégant" and 
I need to create a function to return just "tres elegant". 
Considering we need to take care about unicode chars, what is 
the best way to write a D code to handle that ?


Cheers


import std.stdio;
import std.algorithm;
import std.uni;
import std.conv;

void main()
{
auto str = "très élégant";
immutable accents = unicode.Diacritic;
auto removed = str
.normalize!NFD
.filter!(c => !accents[c])
.to!string;
writeln(removed);  // prints "tres elegant"
}

This first decomposes all characters into base and diacritic, and 
then removes the latter.

Re: Is there Typeof template ?

[Temtaime via Digitalmars-d-learn]

On Friday, 28 October 2016 at 12:44:20 UTC, Adam D. Ruppe wrote:

On Friday, 28 October 2016 at 10:52:05 UTC, Temtaime wrote:

Are there something or should I create a PR to phobos?


Why would you want that?


I have UDAs with values à la @(`str`, 123) uint k;

And i want to know a type of a value.

Re: Is TDPL an accurate description of the D language today?

[rikki cattermole via Digitalmars-d-learn]

On 29/10/2016 1:35 AM, Mark wrote:

On Tuesday, 27 September 2016 at 17:53:39 UTC, Steven Schveighoffer wrote:

On 9/27/16 1:38 PM, Mark wrote:

I've been going through Andrei's excellent book and I noticed that the
latest printing is from 2010. Since D is still a very young language I
can imagine it changing quite a bit within six years. So I wonder if
there are any major inconsistincies between the current state of the
language and its description in TDPL. Is there a list somewhere with all
the changes made in the langauge since the book was published?

Thanks a lot.


Most things that are "wrong" in the book should be in the errata:
http://erdani.com/tdpl/errata/

There are also some things that are not wrong in the book, but have
not been implemented.

I think the most glaring difference is that "clear" has been renamed
to "destroy".

-Steve


Another thing that I found today is that the book suggests nested
structs within functions are of little use. I guess Voldemort types were
introduced into the language after the book was published.

Should this be on the errata page? It's not exactly an error.


Ranges were the 'big' idiom that changed this.
Otherwise they are indeed of little use.

I think it shouldn't be included, but since you feel otherwise, email 
Andrei and let him know, no harm either way :)

Re: Is there Typeof template ?

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

On Friday, 28 October 2016 at 10:52:05 UTC, Temtaime wrote:

Are there something or should I create a PR to phobos?


Why would you want that?

Re: Is TDPL an accurate description of the D language today?

[Mark via Digitalmars-d-learn]

On Tuesday, 27 September 2016 at 17:53:39 UTC, Steven 
Schveighoffer wrote:

On 9/27/16 1:38 PM, Mark wrote:
I've been going through Andrei's excellent book and I noticed 
that the
latest printing is from 2010. Since D is still a very young 
language I
can imagine it changing quite a bit within six years. So I 
wonder if
there are any major inconsistincies between the current state 
of the
language and its description in TDPL. Is there a list 
somewhere with all

the changes made in the langauge since the book was published?

Thanks a lot.


Most things that are "wrong" in the book should be in the 
errata: http://erdani.com/tdpl/errata/


There are also some things that are not wrong in the book, but 
have not been implemented.


I think the most glaring difference is that "clear" has been 
renamed to "destroy".


-Steve


Another thing that I found today is that the book suggests nested 
structs within functions are of little use. I guess Voldemort 
types were introduced into the language after the book was 
published.


Should this be on the errata page? It's not exactly an error.

Re: Avoiding GC

[hardreset via Digitalmars-d-learn]

On Thursday, 27 October 2016 at 07:52:09 UTC, Guillaume Piolat 
wrote:

On Wednesday, 26 October 2016 at 08:18:07 UTC, hardreset wrote:
Is there a page somewhere on how to program D without using 
the GC?


The information is scattered.


How do I allocate / free structs / classes on the heap 
manually?


Classes => 
https://github.com/AuburnSounds/dplug/blob/master/core/dplug/core/nogc.d#L122


Thanks.

I notice you avoid GC altogether in dplug. Whats the reason for 
total avoidance as apposed to just avoiding it in the real time 
code?

Re: Pattern matching in D?

[Nick Treleaven via Digitalmars-d]

On Monday, 24 October 2016 at 04:14:52 UTC, Nick Sabalausky wrote:
It's just...I mean, yea, it works, and you could probably DRY 
it up a little with a type contructing template ("alias 
RgbColor = DoMagic!RgbColor_"), but...meh...


I think the following should be better. Instead of Proxy we would 
have a bespoke mixin which might fix some of the workarounds 
below. In the unittest, using with(Color) should help, but I 
couldn't get that to compile (visit thinks invalid lambdas are 
being passed).


import std.variant;

struct Color {
struct Custom
{
float red;
float green;
float blue;
}

//mixin NewTypes!`Red, Yellow, Green`;
struct Red {}
struct Yellow {}
struct Green {}

private auto impl = Algebraic!(
Custom,
Red,
Yellow,
Green)();
import std.typecons;
mixin Proxy!impl;
}

unittest{
Color color;
// assignment works but not ctor
color = Color.Custom(1, 2, 3);
assert(color.type == typeid(Color.Custom));
// FIXME: currently need impl
auto x = color.impl.visit!(
(Color.Red) => "red",
(Color.Yellow) => "yellow",
(Color.Green) => "green",
(Color.Custom c) =>
ctFormat!`rgb(%s, %s, %s)`(c.red, c.green, c.blue)
);
assert(x == "rgb(1, 2, 3)");
}

// TODO: implement ct parsing
auto ctFormat(string s, Args...)(Args args){
import std.format;
return format(s, args);
}

Re: Default struct member initializer ?

[John Colvin via Digitalmars-d]

On Friday, 28 October 2016 at 11:37:52 UTC, Temtaime wrote:

But what about the case when default ctor is disabled ?


Only relevant if you've written something like `@disable static S 
init();`, which you shouldn't be doing anyway. `.init` is 
independent of `@disable this()`

Re: Fun: Shooting yourself in the foot in D

[John Colvin via Digitalmars-d]

On Thursday, 27 October 2016 at 19:49:16 UTC, Ali Çehreli wrote:


  
http://www.toodarkpark.org/computers/humor/shoot-self-in-foot.html


Some entries for reference:

C
- You shoot yourself in the foot.
- You shoot yourself in the foot and then nobody else can 
figure out what you did.


C++
- You accidentally create a dozen instances of yourself and 
shoot them all in the foot. Providing emergency medical 
assistance is impossible since you can't tell which are bitwise 
copies and which are just pointing at others and saying, 
"That's me, over there."


Python
- You shoot yourself in the foot and then brag for hours about 
how much more elegantly you did it than if you had been using C 
or (God forbid) Perl.


What would the entry for D be? :)

Ali


You unregister your feet from the runtime in order to move 
smoothly, wander in front of a bullet that's paused by the GC, 
which then un-pauses and hits you in the foot.

Re: Best approach to handle accented letters

[Chris via Digitalmars-d-learn]

On Friday, 28 October 2016 at 11:24:28 UTC, Alfred Newman wrote:

Hello,

I'm getting some troubles to replace the accented letters in a 
given string with their unaccented counterparts.


Let's say I have the following input string "très élégant" and 
I need to create a function to return just "tres elegant". 
Considering we need to take care about unicode chars, what is 
the best way to write a D code to handle that ?


Cheers


You could try something like this. It works for accents. I 
haven't tested it on other characters yet.


import std.stdio;
import std.algorithm;
import std.array;
import std.conv;

enum
{
  dchar[dchar] _accent = ['á':'a', 'é':'e', 'è':'e', 'í':'i', 
'ó':'o', 'ú':'u', 'Á':'A', 'É':'E', 'Í':'I', 'Ó':'O', 'Ú':'U']

}

void main()
{
  auto str = "très élégant";
  auto removed = to!string(str.map!(a => (a in _accent) ? 
_accent[a] : a));

  writeln(removed);  // prints "tres elegant"
}

Re: Default struct member initializer ?

[Temtaime via Digitalmars-d]

But what about the case when default ctor is disabled ?

Re: Default struct member initializer ?

[Temtaime via Digitalmars-d]

On Friday, 28 October 2016 at 11:23:47 UTC, John Colvin wrote:

On Friday, 28 October 2016 at 11:20:50 UTC, Temtaime wrote:

Hi !

Is there such a magic ?

struct S { uint k = 2; }

enum Value = Foo!(S.k); // Value == 2

Thanks.


struct S { int k = 2; }

enum Value = S.init.k;

static assert (Value == 2);


Oh i see, thanks

Re: Fun: Shooting yourself in the foot in D

[Guillaume Piolat via Digitalmars-d]

On Thursday, 27 October 2016 at 19:49:16 UTC, Ali Çehreli wrote:


  
http://www.toodarkpark.org/computers/humor/shoot-self-in-foot.html


Some entries for reference:

C
- You shoot yourself in the foot.
- You shoot yourself in the foot and then nobody else can 
figure out what you did.


C++
- You accidentally create a dozen instances of yourself and 
shoot them all in the foot. Providing emergency medical 
assistance is impossible since you can't tell which are bitwise 
copies and which are just pointing at others and saying, 
"That's me, over there."


Python
- You shoot yourself in the foot and then brag for hours about 
how much more elegantly you did it than if you had been using C 
or (God forbid) Perl.


What would the entry for D be? :)

Ali


When you try shooting at your foot with your AK-47, you realize 
the GC has blown it already.

Re: Default struct member initializer ?

[John Colvin via Digitalmars-d]

On Friday, 28 October 2016 at 11:20:50 UTC, Temtaime wrote:

Hi !

Is there such a magic ?

struct S { uint k = 2; }

enum Value = Foo!(S.k); // Value == 2

Thanks.


struct S { int k = 2; }

enum Value = S.init.k;

static assert (Value == 2);

Default struct member initializer ?

[Temtaime via Digitalmars-d]

Hi !

Is there such a magic ?

struct S { uint k = 2; }

enum Value = Foo!(S.k); // Value == 2

Thanks.

Best approach to handle accented letters

[Alfred Newman via Digitalmars-d-learn]

Hello,

I'm getting some troubles to replace the accented letters in a 
given string with their unaccented counterparts.


Let's say I have the following input string "très élégant" and I 
need to create a function to return just "tres elegant". 
Considering we need to take care about unicode chars, what is the 
best way to write a D code to handle that ?


Cheers

Re: The DLang UPB Languages and Systems Research Scholarship

[Chris via Digitalmars-d-announce]

On Tuesday, 25 October 2016 at 22:15:38 UTC, Andrei Alexandrescu 
wrote:
The D Language Foundation is proud to announce its first 
scholarship, offered to CS and EE students at University 
"Politehnica" Bucharest in Romania. More details here:


http://dlang.org/dlangupb-scholarship.html

We are very excited about this program and hope to extend it to 
other universities in the future.



Thanks,

Andrei


A project D > WebAssembley would be great.

Is there Typeof template ?

[Temtaime via Digitalmars-d-learn]

Hi !
Tried to find
alias Typeof(alias A) = typeof(A);
or something, but failed.

Are there something or should I create a PR to phobos?
Thanks

Re: The DLang UPB Languages and Systems Research Scholarship

[thedeemon via Digitalmars-d-announce]

On Wednesday, 26 October 2016 at 01:11:05 UTC, Mike Parker wrote:

For anyone tempted to share this on /r/programming, please 
wait! I hope to do a blog post about this on Friday, so I'll 
post to reddit then. Thanks!


Please don't. This is a total offtopic for /r/programming, don't 
create the reputation "dlang seeks for attention and spams with 
irrelevant stuff".

Re: Fun: Shooting yourself in the foot in D

[Chris via Digitalmars-d]

On Friday, 28 October 2016 at 09:55:34 UTC, Patric Dexheimer 
wrote:

On Friday, 28 October 2016 at 09:29:41 UTC, Chris wrote:
On Friday, 28 October 2016 at 01:25:55 UTC, Kirill Kryukov 
wrote:




You shoot yourself in a tuple containing your foot, boot and 
sock.


Cannot implicitly convert expression (map(shoot(foot))) of 
type MapResult to std.ouch.InputRange!limb


You create the bullet in your foot for efficiency (CTFE).


You shoot yourself in the foot, but it doesn't matter, it was 
allocated on the stack.

dub build --force but only for this package

[Nicholas Wilson via Digitalmars-d-learn]

So I'm trying to debug a project with the work flow of
ssh into remote box
edit/compile/run
if it hangs yank the power out
repeat

this appears to corrupt the the last modification time to some 
time in the future and leads to the warning
File '../.dub/packages/vibe-d-0.7.29/vibe-d/libvibe-d_diet.a' was 
modified in the future. Please re-save.

repeated a bunch.

this also affect the files in my project, and dub is refusing to 
do a non --force'd build.


Is there a way to force dub to rebuild the current package, but 
not its dependencies, to reduce the time to compile?

Re: Fun: Shooting yourself in the foot in D

[Patric Dexheimer via Digitalmars-d]

On Friday, 28 October 2016 at 09:29:41 UTC, Chris wrote:
On Friday, 28 October 2016 at 01:25:55 UTC, Kirill Kryukov 
wrote:




You shoot yourself in a tuple containing your foot, boot and 
sock.


Cannot implicitly convert expression (map(shoot(foot))) of type 
MapResult to std.ouch.InputRange!limb


You create the bullet in your foot for efficiency (CTFE).

Re: Fun: Shooting yourself in the foot in D

[Chris via Digitalmars-d]

On Friday, 28 October 2016 at 01:25:55 UTC, Kirill Kryukov wrote:



You shoot yourself in a tuple containing your foot, boot and 
sock.


Cannot implicitly convert expression (map(shoot(foot))) of type 
MapResult to std.ouch.InputRange!limb

Re: SoundTab Theremin software synthesizer

[Vadim Lopatin via Digitalmars-d-announce]

On Friday, 28 October 2016 at 08:28:41 UTC, Vadim Lopatin wrote:
I've open sourced my project SoundTab: 
https://github.com/buggins/soundtab/


Play like on Theremin, but instead of moving hand in the air, 
move pen over wacom tablet. Volume is modulated by pen pressure,

instead of left hand movement in Theremin.

For better experience, use Wacom digitizer with pressure 
detection.


You can play with mouse as well, but w/o volume modulation (no 
pressure information), and less precise positioning.



Supports only Windows so far.

Binaries may be downloaded here: 
https://github.com/buggins/soundtab/releases



Reddit: 
https://www.reddit.com/r/programming/comments/59thwr/soundtab_theremin_software_synth_with_wacom/
Screenshot added: 
https://buggins.github.io/soundtab/screenshots/soundtab-screenshot-1.png

Re: [Slides] Generic Low Level Programming with D - The Better C for your Business

[Ilya Yaroshenko via Digitalmars-d-announce]

On Friday, 28 October 2016 at 08:28:31 UTC, Johan Engelen wrote:
On Friday, 28 October 2016 at 06:46:27 UTC, Ilya Yaroshenko 
wrote:

https://docs.google.com/presentation/d/1w1cQ8vDluglRIt8Qdnm-sY7kqxoKZxbPEWW6tR3lPpo/edit?usp=sharing


Nice :)

Something I noticed on slide 6-8. The call __adEq2 is pretty 
lame, we have our fix ready: 
https://github.com/ldc-developers/ldc/pull/1719


Nice!


(you really should number your slides!)


Done


-Johan

Re: [Slides] Generic Low Level Programming with D - The Better C for your Business

[Ilya Yaroshenko via Digitalmars-d-announce]

On Friday, 28 October 2016 at 08:26:03 UTC, FreeSlave wrote:
On Friday, 28 October 2016 at 06:46:27 UTC, Ilya Yaroshenko 
wrote:

https://docs.google.com/presentation/d/1w1cQ8vDluglRIt8Qdnm-sY7kqxoKZxbPEWW6tR3lPpo/edit?usp=sharing


Thanks. Was it for live presentation?


Yes


Is there a video?


Probably no



And where is this fox from?


https://telegram.org/

Re: What is the right level of abstractions for D?

[Joakim via Digitalmars-d]

On Thursday, 27 October 2016 at 17:03:09 UTC, Nick Sabalausky 
wrote:

On 10/27/2016 02:22 AM, Joakim wrote:


1. low-level compiled languages like C++, D, Rust, and Swift, 
meant for

performance and usually experts who want to squeeze it out

2. mid-level bytecode languages like Java and C#, meant for 
the vast
middle of day-to-day programmers to crank out libraries and 
apps that

perform reasonably well

3. high-level "scripting" languages like Ruby and Python, 
meant for
those who don't care too much for performance but just want to 
get

working code

I think D is positioned somewhere between 1 and 2, though 
closer to 1.
However, there is sometimes talk of using D for all three, 
though
perhaps that is only meant as an added benefit for people 
already using

it for 1 or 2, ie those who already know the language better.



You're falling into the common fallacy that those groups are 
mutually exclusive and that a single language can't be 
appropriate for more than one. D is all about proving that 
wrong, and is meant for, and good at, all three.


There are good reasons for this split, and yes, it is probably 
impossible for one language to attract all three groups. You 
could use languages from 1 and 2 for all three, with a bit more 
work, but I don't see many scripts written in C++. :)


The reason for the split is that there are different levels of 
software expertise and performance needs, and each of those 
groups is geared for a different level.  Show templates to a 
scripting user and they probably run away screaming.  D can 
probably do well with groups 1 and 2, but the level of power and 
expertise that is needed for those lower levels will scare away 
people from 3.  Those already using it for 1 and 2 may also be 
comfortable with reusing D for scripting, but that's not 
attracting people from group 3, ie those who only want something 
easy to use and don't want to know the difference between a 
static and dynamic array.


I've noticed that, for many of the people who don't "get" D, 
the problem they're hitting is that they're minds are so 
twisted around by the "polyglot" culture, that they're looking 
for "the one" tiny little niche that D is for, not seeing that, 
and thus missing the whole entire point.


Yes, this has definitely hurt D, being stuck between 1 and 2.  
People from 2 probably look at D and think it's too low-level.  
People from 1 are always looking to squeeze out _more_ 
performance, so the GC is a way for them to just write off D.  
You and I think they're making a mistake, but maybe they're not 
wrong for their own uses.


As I said, the recent push for @nogc and C++ compatibility 
suggests that a renewed effort is being made to focus on group 1, 
particularly when combined with the D benchmarks for regex and 
recently math.  I'm happy in that space between 1 and 2, and the 
recent push to move languages from 2 to AoT compilation suggests 
that is a good place to be.  So maybe group 2 will also come to 
us. :)

SoundTab Theremin software synthesizer

[Vadim Lopatin via Digitalmars-d-announce]

Hello,

I've open sourced my project SoundTab: 
https://github.com/buggins/soundtab/


Play like on Theremin, but instead of moving hand in the air, 
move pen over wacom tablet. Volume is modulated by pen pressure,

instead of left hand movement in Theremin.

For better experience, use Wacom digitizer with pressure 
detection.


You can play with mouse as well, but w/o volume modulation (no 
pressure information), and less precise positioning.



Supports only Windows so far.

Binaries may be downloaded here: 
https://github.com/buggins/soundtab/releases



Best regards,
Vadim

Re: [Slides] Generic Low Level Programming with D - The Better C for your Business

[Johan Engelen via Digitalmars-d-announce]

On Friday, 28 October 2016 at 06:46:27 UTC, Ilya Yaroshenko wrote:

https://docs.google.com/presentation/d/1w1cQ8vDluglRIt8Qdnm-sY7kqxoKZxbPEWW6tR3lPpo/edit?usp=sharing


Nice :)

Something I noticed on slide 6-8. The call __adEq2 is pretty 
lame, we have our fix ready: 
https://github.com/ldc-developers/ldc/pull/1719


(you really should number your slides!)

-Johan

Re: [Slides] Generic Low Level Programming with D - The Better C for your Business

[FreeSlave via Digitalmars-d-announce]

On Friday, 28 October 2016 at 06:46:27 UTC, Ilya Yaroshenko wrote:

https://docs.google.com/presentation/d/1w1cQ8vDluglRIt8Qdnm-sY7kqxoKZxbPEWW6tR3lPpo/edit?usp=sharing


Thanks. Was it for live presentation? Is there a video?

And where is this fox from?

Re: Linus' idea of "good taste" code

[Era Scarecrow via Digitalmars-d]

On Tuesday, 25 October 2016 at 22:53:54 UTC, Walter Bright wrote:
Eliminating loops is something D adds, and goes even further to 
making code a straight line.


 A problem for myself and probably many programmers, is some of 
the tricks like what Linus did simply doesn't come to mind 
because it's not something we'd seen before so we can't model 
after it, and also that you sort of follow the same logic of how 
you'd resolve it because that's how you were taught to resolve it 
or it's how you know to resolve it.


 Often when I go for code I start with commenting the 
steps/breakdown, then I write each section, refactoring and 
cleaning up and shortening naturally are last, but once code is 
working it doesn't usually change too much even if there can be 
improvement.


 Hmm what we really need is something like a good 100 examples of 
good 'tasty' code, good code in a variety of code, something 
digestible and even explained down for those not following the 
full logic if how/why it works, perhaps even bad examples to work 
up from.

Re: [Slides] Generic Low Level Programming with D - The Better C for your Business

[e-y-e via Digitalmars-d-announce]

On Friday, 28 October 2016 at 06:46:27 UTC, Ilya Yaroshenko wrote:

https://docs.google.com/presentation/d/1w1cQ8vDluglRIt8Qdnm-sY7kqxoKZxbPEWW6tR3lPpo/edit?usp=sharing


Thanks for uploading these!

Re: test if the alias of a template is a literal

[Gianni Pisetta via Digitalmars-d-learn]

On Friday, 28 October 2016 at 03:33:33 UTC, Basile B. wrote:

Hello, I think the correct isStringLiteral would be:

import
std.meta;

template isStringLiteral(alias V)
{
enum isCompileTime = is(typeof((){enum a = V;}));
enum isString = is(typeof(V) == string);
enum isStringLiteral = isCompileTime && isString;
}



It works, Thanks. Also, i don't think in my case there is the 
need for a variant for types( aka isStringLiteral(V) without 
alias) because it's an error to pass a type to Optimize in first 
place. But for a general purpouse library, maybe a template 
isLiteral(alias V) that only checks if it is a literal without 
the type checking, would have more sense to have also 
isLiteral(V) for types that returns always false.


Gianni Pisetta

Re: How to kill whole application if child thread raises an exception?

[dm via Digitalmars-d-learn]

On Thursday, 27 October 2016 at 13:37:29 UTC, Steven 
Schveighoffer wrote:


Hm... what about:

import std.traits: Parameters;

auto mySpawn(F)(F func, Parameters!F params)
{
static auto callIt(F func, Parameters!F params)
{
try
{
return func(params);
}
catch(Throwable t)
{
// print the exception/error, e.g.:
import std.writeln;
writeln(e.toString());
// terminate program
import core.stdc.stdlib : exit;
exit(1);
}
}

return spawn(, func, params);
}

void main()
{
auto tID = mySpawn();
...
}

-Steve


I found the solution which works with dmd and ldc2:

...
import core.stdc.stdlib: _Exit;
_Exit(exitcode);
...

[Slides] Generic Low Level Programming with D - The Better C for your Business

[Ilya Yaroshenko via Digitalmars-d-announce]

https://docs.google.com/presentation/d/1w1cQ8vDluglRIt8Qdnm-sY7kqxoKZxbPEWW6tR3lPpo/edit?usp=sharing

Re: exercise - find invalid D tokens (Impossible ?)

[Basile B. via Digitalmars-d-learn]

On Friday, 28 October 2016 at 06:21:38 UTC, Johan Engelen wrote:

On Friday, 28 October 2016 at 05:16:45 UTC, Basile B. wrote:

Here are the specifications of token strings:

"Token strings open with the characters q{ and close with the 
token }. In between must be valid D tokens. The { and }"


So we can deduce that any invalid D token inside a token 
string will lead to a compilation error. Indeed:


void main()
{
enum s = q{#}; // malformed special token sequence
}

produces an error.

So are you able to find more invalid token ?


Try  '}'


Yes and many others. Since I've posted this message I've realized 
that actually there are much invalid tokens. Any character that's 
not an Universal Alpha and that's not in a string prevents 
compilation.


A complete list is at page 451 in 
http://www.open-std.org/JTC1/SC22/WG14/www/docs/n1124.pdf

Re: Mir GLAS is a C library and passes Natlib's test suite! And questions :-)

[Ilya Yaroshenko via Digitalmars-d]

On Friday, 28 October 2016 at 03:44:05 UTC, Andrei Alexandrescu 
wrote:

On 10/27/16 3:59 AM, Ilya Yaroshenko wrote:
Mir GLAS (Generic Linear Algebra Subprograms) has its own 
repository [1]

now.

Big news:

1. Mir GLAS does not require D / C++ runtime and can be used 
in any
programming language as common C library! See read README [1] 
for more

details.


Cool work!

One thing I'd want to understand is how to use Mir GLAS from 
within D itself. If it's a straight C interface, there seems to 
be a fair amount of friction (we have a D program communicating 
with a D library through the uncomfortable confines of a C 
interface). Is that the case? Should there be a way to short 
circuit the C API and use a more expressive D interface? 
(Looking e.g. at Eigen, it's meant to allow people using it 
from C++ to take advantage of a C++-specific smooth interface.)


GLAS has 2 APIs: GLAS(ndslise) and BLAS(fortran).
Both APIs has C/C++ and D headers. D headers contains aliases 
with unified names like in core.stdc.tgmath. So, extern(C) 
interface for GLAS is comfortable and looks like:


gemm(alpha, a, b, beta, c); // calls glas_?gemm

The latest ndslice PR to stable branch solves a problem in case 
of const and immutable a and b. 
https://github.com/dlang/phobos/pull/4873


GLAS does not have syntax like Eigen, i mean

c = a * b;

This syntax can be a part of another package for scripting like 
syntax.
See also Q 
https://github.com/libmir/mir-glas#why-glas-does-not-have-lazy-evaluation-and-aliasing-like-eigen


6. GLAS is no longer distributed as a generic library. Level 2 
and Level
3 generic API will be removed from Mir. There are few reasons 
why it is
much better as precompiled library, and no reasons why it 
should be
generic. In the same time, generic multidimensional Level 1 
routines

will be improved.


I guess I'd like to understand the dynamics better here.


The main reason is compilation time (1 secs+) and template bloat 
(50 KB +). OpenBLAS size is more than 20 MB. GLAS is smaller, but 
it is not something lightweight like `sort`.
Assume you are buildings a large D projects one-by-one file in 
parallel. It can be builded during minutes and its size can be 
>100 MB, only because GLAS.


So, having an extern(C) layers is good practice to keep interface 
clear and compile time small.



Questions:

1. Would you like GLAS be packed with Phobos?


You have all support from Walter and myself for integrating 
GLAS with Phobos. Before that I'd want to make sure we slice 
and dice things properly.


Awesome! I am happy to read this)

2. Is it possible to make GLAS a replaceable part of Phobos? 
For example
a user may want to use the latest GLAS without waiting a new 
compiler

release.


That would be an interesting precedent. We should talk about it 
next week. (My knee-jerk reaction is if we're worth our salt we 
should release Phobos often enough to obviate the need for 
this. But the notion of hot-swapping subcomponents is cool too.)


Some concepts can be found on a slides from my today's talk
https://docs.google.com/presentation/d/1w1cQ8vDluglRIt8Qdnm-sY7kqxoKZxbPEWW6tR3lPpo/edit?usp=sharing


Thanks,

Andrei


Best regards,
Ilya

Re: exercise - find invalid D tokens (Impossible ?)

[Johan Engelen via Digitalmars-d-learn]

On Friday, 28 October 2016 at 05:16:45 UTC, Basile B. wrote:

Here are the specifications of token strings:

"Token strings open with the characters q{ and close with the 
token }. In between must be valid D tokens. The { and }"


So we can deduce that any invalid D token inside a token string 
will lead to a compilation error. Indeed:


void main()
{
enum s = q{#}; // malformed special token sequence
}

produces an error.

So are you able to find more invalid token ?


Try  '}'

Re: Comparing compilation time of random code in C++, D, Go, Pascal and Rust

[Sebastien Alaiwan via Digitalmars-d-announce]

On Thursday, 27 October 2016 at 12:11:09 UTC, Johan Engelen wrote:

On Thursday, 27 October 2016 at 06:43:15 UTC, Sebastien Alaiwan
If code generation/optimization is the bottleneck, a 
"ccache-for-D" ("dcache"?) tool might be very beneficial.


See 
https://johanengelen.github.io/ldc/2016/09/17/LDC-object-file-caching.html


I also have a working dcache implementation in LDC but it still 
needs some polishing.
Hashing the LLVM bitcode ... how come I didn't think about this 
before!
Unless someone manages to do the same thing with gdc + GIMPLE, 
this could very well be the "killer" feature of LDC ...


Having a the fastest compiler on earth still doesn't provide 
scalability ; interestingly, when I build a full LLVM+LDC 
toolchain, the longest step is the compilation of the dmd 
frontend. It's the only part that is:

1) not cached: all the other source files from LLVM are ccache'd.
2) sequential: my CPU load drops to 12.5%, although it's near 
100% for LLVM.