Hi everyone !
Let's say I have a struct :
struct Test
{
immutable (ubyte)[] data;
T get(T)()
{
return *(cast(T*)(&(data[0])));
}
}
This code will work :
import std.stdio;
void main()
{
Test t;
t.data = [152, 32, 64, 28, 95];
On Saturday, 19 April 2014 at 17:49:54 UTC, bearophile wrote:
matovitch:
struct Test
{
immutable (ubyte)[] data;
T get(T)()
{
return *(cast(T*)(&(data[0])));
}
It's better to return const/immutable data. Otherwise the
program gives undefined r
On Saturday, 19 April 2014 at 18:46:28 UTC, matovitch wrote:
On Saturday, 19 April 2014 at 17:49:54 UTC, bearophile wrote:
matovitch:
I did'nt know that one.
This last sentence is misleading, let be clear : I know almost
nothing when it comes to D...but I'm willing to learn ! ;-)
On Saturday, 19 April 2014 at 18:46:28 UTC, matovitch wrote:
On Saturday, 19 April 2014 at 17:49:54 UTC, bearophile wrote:
matovitch:
struct Test
{
immutable (ubyte)[] data;
T get(T)()
{
return *(cast(T*)(&(data[0])));
}
It's better to return
On Sunday, 20 April 2014 at 00:55:31 UTC, David Held wrote:
On 4/19/2014 3:31 PM, Andrej Mitrovic via Digitalmars-d-learn
wrote:
[...]
struct S
{
int get() { return 0; }
T get(T)() { return T.init; }
}
void main()
{
S s;
float x = s.get(); // which overload? (currently int
ge
On Sunday, 20 April 2014 at 08:28:07 UTC, monarch_dodra wrote:
On Sunday, 20 April 2014 at 07:52:08 UTC, matovitch wrote:
struct S
{
ubyte get() { return 0 ; }
float get() { return 0.; }
}
void main()
{
S s;
float x = s.get(); // does'nt know which overload, does'nt
compile.
}
W
Hi !
Does anybody knows why dmd segfaults on this code ? Should I
report this as a bug ?
import std.stdio;
enum LiftingGender
{
PREDICT,
UPDATE,
}
struct Test(float[][] coeffs,
int[] offsets,
LiftingGender gender)
{
immutable float[][] coeffs = coeffs;
On Saturday, 31 May 2014 at 17:01:23 UTC, bearophile wrote:
matovitch:
Does anybody knows why dmd segfaults on this code ? Should I
report this as a bug ?
Please report this minimized case to Bugzilla:
struct Foo(int[] arr) {
const int[] arr = arr;
}
void main() {
Foo!([0]) foo;
}
In fact it segfauls on any template parameter if it has the same
name as the immutable member (at least it's coherent). Something
as simple as :
struct Foo(int i)
{
immutable int i = i;
}
void main()
{
Foo!5 foo;
writeln(foo);
}
I am suprised that nobody tried this before. BTW I a
I remembered my psswd don't take my last sentence into account (i
will filed this).
I updated the issue. Strangely if done in the main everything is
fine :
Error: undefined identifier i
I was looking for a workaround to multiple alias this (or
opImplicitCast) the following trick doesn't work (why shouldn't
it ?). The error message is quite obscure to me.
import std.stdio;
class A(Derived)
{
alias cast(ref Derived)(this).x this;
}
class B : A!B
{
float x;
}
class C
On Wednesday, 11 June 2014 at 20:53:21 UTC, Jonathan M Davis via
Digitalmars-d-learn wrote:
I don't believe that it's legal to use a cast in an alias
declaration, and
that's certainly what the error seems to be indicating. Also,
using ref in a
cast is definitely illegal regardless of where the
If I quote de documentation :
"Any casting of a class reference to a derived class reference is
done with a runtime check to make sure it really is a downcast.
null is the result if it isn't. Note: This is equivalent to the
behavior of the dynamic_cast operator in C++."
I explicitly kept tra
On Monday, 24 November 2014 at 22:50:33 UTC, bearophile wrote:
In some D programs I'm using this coding pattern:
You can see an example of this pattern that I've used here:
http://rosettacode.org/wiki/Solve_a_Hopido_puzzle#D
Bye,
bearophile
Awesome gist and great pattern ! Sometimes your foru
Hi,
It's been a long time since I coded some d code... sorry I take
the lazy way asking for advices. :D
Lets say I want to implement some generic algorithm. I would like
to checks the types passed to my algorithm implements a specific
interface.
interface IStuff(Stuff)
{
void foo();
}
cla
More like :
import std.stdio;
interface IStuff(Stuff)
{
void foo();
}
class TypeClass(T, I) : I(T)
{
alias this stuff;
T stuff;
}
void myAwesomeAlgo(Stuff) (TypeClass!(Stuff, IStuff) stuff)
{
stuff.foo();
}
struct MyStuff
{
void foo()
{
writeln("Hello World
Well, just follow that link to the code...it almost compile :
http://dpaste.com/3JNP0QD.
well, alias this is the issue here.
interface I
{
void foo();
}
struct S
{
void foo() {}
}
class C : I
{
S s;
alias this s;
}
don't compile...if you have any idea to do otherwise I am greatly
interested. Thanks !
On Tuesday, 24 March 2015 at 15:45:36 UTC, Dennis Ritchie wrote:
Tell me, please, how can I replace this code?
import std.conv : to;
import std.bigint : BigInt;
import std.string : format;
import std.stdio : writeln;
void main() {
BigInt[10] bitArr;
ulong n = 18_446_724_073_70
To resume my goal (last lonely message I promise), how can you
statically check a type implement an interface without making
this type inherit the interface (otherwise std.traits would do
it) ?
ps : it seems to me that this is exactly what the haskell
compiler do with type classes <- layman o
Wait no ! In that case my type will have to inherit the
interface...I don't want that, checking without inheriting...I
know thats weird.
On Tuesday, 24 March 2015 at 16:44:54 UTC, weaselcat wrote:
On Tuesday, 24 March 2015 at 15:51:00 UTC, matovitch wrote:
Hi,
It's been a long time since I coded some d code... sorry I take
the lazy way asking for advices. :D
Lets say I want to implement some generic algorithm. I would
like
to
On Tuesday, 24 March 2015 at 17:28:50 UTC, Dennis Ritchie wrote:
On Tuesday, 24 March 2015 at 16:35:04 UTC, Ivan Kazmenko wrote:
What exactly is not working?
Everything works. I'm just a little forgotten properties of the
operation xor.
I just wanted to xor 1 each digit in the number of typ
Thanks for the precisions on template constraint and template
specialization...Indeed wath I want to do look like isInputRange
constraint. Haskell have something like :
//(Pseudo D-Haskell)
void foo(InputRange R)(R r);
//D equivalent
void foo(R)(R r) if (isInputRange(R));
Except they call the
On Wednesday, 25 March 2015 at 08:55:14 UTC, bearophile wrote:
matovitch:
I am curious to know how isInputRange is implemented since I
wanted to do kind of the same but I am afraid it's full of
(ugly)
traits and template trickeries where haskell type classes are
quite neat and essentially a d
Hi,
floats are stored on 32 bits using ieee754...and I would like
(for some obscure reason) to reinterpret a such float into a 32
bits uint (i.e without altering the memory). A simple :
import std.stdio;
void main()
{
float f = 0.5;
uint i = cast(uint)(f);
writeln(i);
}
doesn't
On Sunday, 29 March 2015 at 13:39:47 UTC, matovitch wrote:
Hi,
floats are stored on 32 bits using ieee754...and I would like
(for some obscure reason) to reinterpret a such float into a 32
bits uint (i.e without altering the memory). A simple :
import std.stdio;
void main()
{
float f =
On Sunday, 29 March 2015 at 14:50:24 UTC, ketmar wrote:
On Sun, 29 Mar 2015 13:45:10 +, matovitch wrote:
you can also use unions.
Good idea ! In my case I think it was better to cast, but this
could be helpful another time thanks ! :)
Hi,
Surely I am misunderstanding something.
I got something like this :
struct S
{
void opAssign(const ref s)
{
//...
}
}
S genS()
{
S s;
//...
return s;
}
main()
{
S s;
s = genS();
}
DMD says : ...opAssign (ref const(S) point) is not callable using
a
void opAssign(const ref s) should be void opAssign(const ref S s)
btw and btw bis, I should probably make it const ref
SopAssign(const ref S s) :/ I stop flooding there.
The title should be assignement not copy.
On Monday, 30 March 2015 at 17:14:27 UTC, Adam D. Ruppe wrote:
On Monday, 30 March 2015 at 17:09:14 UTC, matovitch wrote:
(I am gessing ref argument explitly means no rvalue)
That's right. I'd first say don't use ref, just use "const S"
and it will work and probably do what you need efficient
On Monday, 30 March 2015 at 17:21:53 UTC, Steven Schveighoffer
wrote:
Annoying as this is (and blatantly awkward), it saves
you from having to implement twice:
void opAssign(T)(auto ref const T s) if(is(T == S)) {...}
Yep, this seems awkward to me too thought according to Adam one
can do :
(it's not on line 79 obviously, you got me :D)
Hi again,
I have this simple toy code :
import point;
import std.random;
import std.algorithm;
import std.functional;
void getRandomPoint(R)(R randVar, ref Point p)
{
p.x = randVar;
p.y = randVar;
p.z = randVar;
}
void main()
{
Point[500] points;
auto randVar = un
On Monday, 30 March 2015 at 18:23:32 UTC, Adam D. Ruppe wrote:
On Monday, 30 March 2015 at 18:07:18 UTC, matovitch wrote:
kmeans_example.d(79): Error: template
std.algorithm.iteration.map
That error is easy: use points[].map!(test) instead of
points.map.
Since points is a static array, it i
On Monday, 30 March 2015 at 18:34:19 UTC, Adam D. Ruppe wrote:
On Monday, 30 March 2015 at 18:29:32 UTC, matovitch wrote:
I tried importing std.range and points.array works too.
Aye, that would work too, but the slice I think is more
efficient as I'm pretty sure... not completely sure, but I
Well I have a bit of a similar problem with foreach.
If I use classic T[] range, I can do :
foreach(int i, auto t, myRange)...
But if I use an Array!T (from std.container) I get :
cannot infer argument types, expected 1 argument, not 2
Even if I add the brackets []. Any idea ? Thanks for your
On Monday, 30 March 2015 at 19:08:24 UTC, anonymous wrote:
On Monday, 30 March 2015 at 18:37:53 UTC, matovitch wrote:
On Monday, 30 March 2015 at 18:34:19 UTC, Adam D. Ruppe wrote:
[...]
Aye, that would work too, but the slice I think is more
efficient as I'm pretty sure... not completely sure
Language ref -> Array -> Slice
"An array slice does not copy the data, it is only another
reference to it."
So the total slice of a static array is a range using the
underlying memory of the static array isnt it ?
Thanks. On a sader note, I found a respons'less thread about my
second question :
http://forum.dlang.org/thread/mailman.2247.1353945423.5162.digitalmars-d-le...@puremagic.com
"where std.container.Array is concerned: how come I can't use a
foreach(i, x; myArray) formulation? I.e. one where th
On Monday, 30 March 2015 at 19:31:54 UTC, anonymous wrote:
On Monday, 30 March 2015 at 19:03:05 UTC, matovitch wrote:
Well I have a bit of a similar problem with foreach.
If I use classic T[] range, I can do :
foreach(int i, auto t, myRange)...
But if I use an Array!T (from std.container) I g
Hi again again,
ulong u = 1 << 63;
Raise :
Error: shift by 63 is outside the range 0..31
This is a bug isn't it, the ulong are supposed to be on 64 bits ?
I guess it's time I go to bed.
Have a nice night !
On Monday, 30 March 2015 at 22:34:55 UTC, Vladimir Panteleev
wrote:
On Monday, 30 March 2015 at 22:34:00 UTC, matovitch wrote:
Hi again again,
ulong u = 1 << 63;
Raise :
Error: shift by 63 is outside the range 0..31
This is a bug isn't it, the ulong are supposed to be on 64
bits ? I guess i
Hi,
I just learn about auto ref functions and tried this :
import std.stdio;
auto ref foo(int i, ref float f)
{
if (i < f)
{
return i;
}
else
{
return f;
}
}
void main()
{
int i = 1;
float f1 = 1.
(you can remove the ref stuff)
Ok this explain it :
http://dlang.org/function.html#auto-functions. It should return a
float.
In fact I am now thinking it's great...I tried with string
instead of float and got a clear error message. I should have
read the spec more thoroughly.
Hello,
The question is in the title. It should be possible for a finite
random access ranges to perform an indexed foreach no ? I mean
like :
foreach(size_t i = 0, auto ref x; R)
{
/*...*/
}
Why are other foreach statements overloadable but this one ?
Thanks in advance.
On Saturday, 11 April 2015 at 10:53:46 UTC, Jakob Ovrum wrote:
On Saturday, 11 April 2015 at 10:50:17 UTC, matovitch wrote:
Hello,
The question is in the title. It should be possible for a
finite random access ranges to perform an indexed foreach no ?
I mean like :
foreach(size_t i = 0, aut
On Saturday, 11 April 2015 at 11:24:32 UTC, John Colvin wrote:
On Saturday, 11 April 2015 at 11:03:28 UTC, matovitch wrote:
On Saturday, 11 April 2015 at 10:53:46 UTC, Jakob Ovrum wrote:
On Saturday, 11 April 2015 at 10:50:17 UTC, matovitch wrote:
Hello,
The question is in the title. It shoul
On Saturday, 11 April 2015 at 14:01:07 UTC, John Colvin wrote:
What OS are you on?
Ubuntu 14.10.
Thanks for the tip ! I was looking at something like this.
54 matches
Mail list logo
