Re: Reflection in D
On Saturday, 28 January 2017 at 07:10:27 UTC, medhi558 wrote:
I have a last question, currently i use :
if(lc.name.indexOf("protocol.messages") != -1)
To know if the class is a NetworkMessage, Would be possible to
do this
if(lc is NetworkMessage)
Sorry for my English, i speak french.
if (auto nm = cast(NetworkMessage)lc)
{
//do something with nm
}
Re: Reflection in D
I have a last question, currently i use :
if(lc.name.indexOf("protocol.messages") != -1)
To know if the class is a NetworkMessage, Would be possible to do
this
if(lc is NetworkMessage)
Sorry for my English, i speak french.
Re: Reflection in D
I develop a game server. Currently I use a switch :
import protocol.messages.connection.Message1;
import protocol.messages.connection.Message2;
import protocol.messages.queues.Message3;
import ..
import protocol.messages.NetworkMessage;
class ProtocolMessageManager
{
public static NetworkMessage GetInstance(uint id)
{
switch(id)
{
case Message1.Id:
return new Message1();
case Message2.Id:
return new Message2();
.
default:
return null;
}
}
}
what I want to do :
import protocol.messages.NetworkMessage;
class ProtocolMessageManager
{
private static TypeInfo_Class[uint] m_types;
public static void Init()
{
foreach(mod; ModuleInfo)
{
foreach(TypeInfo_Class lc; mod.localClasses)
{
if(lc.name.indexOf("protocol.messages") != -1)
{
NetworkMessage c =
cast(NetworkMessage)lc.create();
ProtocolMessageManager.m_types[c.MessageId] = lc;
}
}
}
}
public static NetworkMessage GetInstance(string id)
{
auto v = (id in ProtocolMessageManager.m_types);
if (v !is null)
return
cast(NetworkMessage)ProtocolMessageManager.m_types[id].create();
else
return null;
}
}
Re: Partial arrays reclaimed?
On Friday, 27 January 2017 at 23:36:58 UTC, Stefan Koch wrote: It should reclaim the memory from the beginning of the array. I doubt the current implementation will though, you should check.
Concurrent containers
Does phobos offer concurrent containers? I couldn't find one at http://dlang.org/phobos/std_container.html Any other in the D land? Arun
Re: Partial arrays reclaimed?
On Friday, 27 January 2017 at 23:22:17 UTC, Nick Sabalausky wrote: Suppose an array is being used like a FIFO: --- T[] slice; // Add: slice ~= T(); // Remove: slice = slice[1..$]; --- Assuming of course there's no other references to the memory, as this gets used, does the any of the memory from the removed elements ever get GC'd? Also, if this is a long-running process, isn't there a potential danger in the array just marching through the address space and running out of room? (ie either running out of of continuous space, or hitting 0xFFF) It should reclaim the memory from the beginning of the array. But your could just have written a small tool that does this and look at the memory use over time. Generally a good idea, to perform experiments with things you are interested in. And there is always the risk of running out of memory on machines which have no mmu.
Partial arrays reclaimed?
Suppose an array is being used like a FIFO: --- T[] slice; // Add: slice ~= T(); // Remove: slice = slice[1..$]; --- Assuming of course there's no other references to the memory, as this gets used, does the any of the memory from the removed elements ever get GC'd? Also, if this is a long-running process, isn't there a potential danger in the array just marching through the address space and running out of room? (ie either running out of of continuous space, or hitting 0xFFF)
Re: D package for optimizing/compressing images
On 01/27/2017 03:03 AM, aberba wrote: Are there any dub package for compressing images uploaded through web forms? Cropping/resizing may also come in handy. I want one for a vibe.d project. I have a minimal MagickWand binding if you want to use or extend: https://github.com/acehreli/alibum/blob/master/magickwand.d Ali
Re: D package for optimizing/compressing images
On Friday, 27 January 2017 at 19:14:19 UTC, Jesse Phillips wrote: On Friday, 27 January 2017 at 11:03:15 UTC, aberba wrote: Are there any dub package for compressing images uploaded through web forms? Cropping/resizing may also come in handy. I want one for a vibe.d project. I don't know of any D projects. If I were doing this I'd be running the vibe.d server on linux and just use common linux utilities for photo manipulation on the commandline. Unfortunately, I will be using Heroku which is a PaaS, so no access to shell.
Re: Reflection in D
On Friday, 27 January 2017 at 21:02:13 UTC, medhi558 wrote: Hello, I would like to know if it is possible to recover all classes in the project in D. Yes, `foreach(mod; ModuleInfo) foreach(lc; mod.localClasses)`... but why do you want it? That facility is kinda limited in doing many things with.
Reflection in D
Hello, I would like to know if it is possible to recover all
classes in the project in D.
Example in c# :
Assembly asm = Assembly.GetAssembly(typeof(MyClass));
foreach (Type type in asm.GetTypes())
{
}
Re: D package for optimizing/compressing images
On Friday, 27 January 2017 at 11:03:15 UTC, aberba wrote: Are there any dub package for compressing images uploaded through web forms? Cropping/resizing may also come in handy. I want one for a vibe.d project. I don't know of any D projects. If I were doing this I'd be running the vibe.d server on linux and just use common linux utilities for photo manipulation on the commandline.
Re: Bug in documentation or misunderstanding it?
On Thu, Jan 26, 2017 at 06:47:21PM +, Suliman via Digitalmars-d-learn wrote:
> On Thursday, 26 January 2017 at 18:42:29 UTC, Suliman wrote:
> > On Thursday, 26 January 2017 at 17:52:24 UTC, H. S. Teoh wrote:
> > > On Thu, Jan 26, 2017 at 05:38:59PM +, Suliman via
> > > Digitalmars-d-learn wrote:
> > > > I read docs and can't understand what's wrong. Or I am do not
> > > > understand it, or there is come mistake.
> > > >
> > > > Let's look at function
> > > > https://dlang.org/phobos/std_stdio.html#.File.byLine
> > > >
> > > > auto byLine(Terminator = char, Char = char)(KeepTerminator
> > > > keepTerminator = No.keepTerminator, Terminator terminator =
> > > > '\x0a')
> > > >
> > > > what does mean first groups of scope: (Terminator = char, Char =
> > > > char) ?
> > >
> > > Those are compile-time parameters. You specify them in a
> > > compile-time argument list using the !(...) construct, for
> > > example:
> > >
> > > auto lines = File("myfile.txt")
> > > .byLine!(dchar, char)(Yes.keepTerminator, '\u263a');
> > >
> > >
> > > T
> >
> > So I am right about others items about for example that `=` is optional?
>
> Why this code is work: `file.byLine(KeepTerminator.no, 'm')`
Yes, the `=` means the parameter has a default value. This applies to
both compile-time parameters and runtime parameters. So:
file.byLine(KeepTerminator.no);
is the same as:
file.byLine!(char, char)(No.keepTerminator, '\x0a');
T
--
There are 10 kinds of people in the world: those who can count in binary, and
those who can't.
Re: A matter of propiety
On Friday, 27 January 2017 at 16:30:14 UTC, WhatMeWorry wrote: But it seems like I'm committing some great sin by doing this. meh i see no problem with it. Just another quick question: is the module that holds the main() function just the same as any other module? It is the same as any other module. I say it should be named the same as any other (including a two-part name, `module foo;` is likely to clash if you ever do two libraries, i almost always use `module myproject.foo;` instead), but all the exact same rules apply.
A matter of propiety
module_common
import app; // Ugly? Bad? Better way?
common_func()
{
static if (compileTimeFlag1)
codeBlockA
static if (compileTimeFlag2)
codeBlockB
static if (compileTimeFlag3)
codeBlockC
}
I want to have many stand-alone programs that calls the common
function.
Each app.d is its own separate directory so I can use the same
name.
app.d
static bool compileTimeFlag1 = true;
common_func()
app.d
static bool compileTimeFlag1 = true;
static bool compileTimeFlag2 = true;
common_func()
app.d
static bool compileTimeFlag1 = true;
static bool compileTimeFlag2 = true;
static bool compileTimeFlag3 = true;
common_func()
I've got this working, but only if I add an "import app;" to
module_common.
Otherwise I get, "Error: undefined identifier compileTimeFlags
I want to keep all the compileTimeFlags in the main modules.
Seems like the
most logical place to put them.
But it seems like I'm committing some great sin by doing this.
Maybe it's my C++ days,
but it just seems wrong to have a module import the main module?
Is there a more elegant
approach?
Just another quick question: is the module that holds the main()
function just the
same as any other module? Or is there some secret sauce?
(Besides the point of entry)
Thanks.
Re: D idom for removing array elements
On Friday, 27 January 2017 at 15:39:57 UTC, cym13 wrote: On Friday, 27 January 2017 at 08:30:41 UTC, Dukc wrote: [...] Note that if the set of values to be excluded isn't smaller than the haystack then using partition is way faster and your method is the slowest of all. If the order of the array matters stable partition can be used but is slower than the original method. [...] I forgot to say that the main reason to use partition is that it's easy to use it to remove the elements of the array in place: auto r = a.partition!(v => !b.canFind(v)); a.length -= r.length; It just puts the "bad" elements at the end and changes the length of the array.
Re: D idom for removing array elements
On Friday, 27 January 2017 at 08:30:41 UTC, Dukc wrote:
On Friday, 27 January 2017 at 08:15:56 UTC, Dukc wrote:
My method is much better for large arrays I tested here.
Trough, considering the size of the arrays the performance
difference should be even greater, like 1000X better instead of
15X better so it's definitely not that great.
Note that if the set of values to be excluded isn't smaller than
the haystack then using partition is way faster and your method
is the slowest of all. If the order of the array matters stable
partition can be used but is slower than the original method.
Added test cases and benchmark results:
void partitionMethod() {
auto c = a.partition!(v => b.canFind(v));
// Sort to recover the order
assert(sort(c[0..4]).array == [1, 2, 5, 7]);
}
void stablePartitionMethod() {
auto c = a.partition!(v => b.canFind(v),
SwapStrategy.stable);
assert(c[0..4] == [1, 2, 5, 7]);
}
benchmark!(originalMethod,
WilsonMethod,
myMethod,
partitionMethod,
stablePartitionMethod)(1)
.each!writeln;
With "a" of length 4000 and "b" of length 4000:
/*
int[] a = [1, 2, 3, 4, 5, 6, 7, 4].cycle.take(4000).array;
int[] b = [3, 4, 6].cycle.take(4000).array;
*/
TickDuration(51482830)
TickDuration(43634792)
TickDuration(1085159) // myMethod is faster
TickDuration(44216820) // 3rd
TickDuration(42920567) // 2nd
With "a" of length 40 and "b" of length 3:
/*
int[] a = [1, 2, 3, 4, 5, 6, 7, 4].cycle.take(40).array;
int[] b = [3, 4, 6];
*/
TickDuration(312038) // 2nd
TickDuration(541912)
TickDuration(606883)
TickDuration(190662) // partitionMethod is way faster
TickDuration(418751) // 3rd
Re: Problems compiling sqlite-d
On Friday, 27 January 2017 at 12:21:29 UTC, Nestor wrote: On Friday, 27 January 2017 at 12:06:33 UTC, Stefan Koch wrote: On Friday, 27 January 2017 at 12:04:06 UTC, Stefan Koch wrote: I take it you build without dub ? Have you specified source/sqlite.d on your compile commandline ? That was supposed to say. sqlite-d/source/sqlited.d Please feel free to post here or contact me directly regarding the usage of sqlite-d. Yes I was building withoug dub. What I did was simply: copy data.db to sqlite-d/source cd to sqlite-d/source copy api_user.d to z1_app.d modify z1_app.d (as shown before) compile z1_app without additional parameters. Shouldn't it work? This was with dmd v2.072.2 on Windows 7 SP1 x86-64 You have to compile the library with your app. or better yet use dub replace app.d with your app.d and run dub
Re: Problems compiling sqlite-d
On Friday, 27 January 2017 at 12:06:33 UTC, Stefan Koch wrote: On Friday, 27 January 2017 at 12:04:06 UTC, Stefan Koch wrote: I take it you build without dub ? Have you specified source/sqlite.d on your compile commandline ? That was supposed to say. sqlite-d/source/sqlited.d Please feel free to post here or contact me directly regarding the usage of sqlite-d. Yes I was building withoug dub. What I did was simply: copy data.db to sqlite-d/source cd to sqlite-d/source copy api_user.d to z1_app.d modify z1_app.d (as shown before) compile z1_app without additional parameters. Shouldn't it work? This was with dmd v2.072.2 on Windows 7 SP1 x86-64
Re: Problems compiling sqlite-d
On Friday, 27 January 2017 at 12:04:06 UTC, Stefan Koch wrote: I take it you build without dub ? Have you specified source/sqlite.d on your compile commandline ? That was supposed to say. sqlite-d/source/sqlited.d Please feel free to post here or contact me directly regarding the usage of sqlite-d.
Re: Problems compiling sqlite-d
On Friday, 27 January 2017 at 12:01:30 UTC, Nestor wrote:
Hi,
I was trying to use https://github.com/UplinkCoder/sqlite-d
Unfortunately even something as simple as this doesn´t compile
(at least on Windows):
import std.stdio, sqlited;
void main(string[] args) {
string filename = (args.length == 2 ? args[1] : "data.db");
Database db = Database(filename);
}
See the error:
OPTLINK (R) for Win32 Release 8.00.17
Copyright (C) Digital Mars 1989-2013 All rights reserved.
http://www.digitalmars.com/ctg/optlink.html
z1_app.obj(z1_app)
Error 42: Symbol Undefined _D7sqlited8Database6__initZ
z1_app.obj(z1_app)
Error 42: Symbol Undefined
_D7sqlited8Database6__ctorMFNcAyabZS7sqlited8Database
Error: linker exited with status 107814472
Is there any other native D implementation of sqlite reader?
I take it you build without dub ?
Have you specified source/sqlite.d on your compile commandline ?
Problems compiling sqlite-d
Hi,
I was trying to use https://github.com/UplinkCoder/sqlite-d
Unfortunately even something as simple as this doesn´t compile
(at least on Windows):
import std.stdio, sqlited;
void main(string[] args) {
string filename = (args.length == 2 ? args[1] : "data.db");
Database db = Database(filename);
}
See the error:
OPTLINK (R) for Win32 Release 8.00.17
Copyright (C) Digital Mars 1989-2013 All rights reserved.
http://www.digitalmars.com/ctg/optlink.html
z1_app.obj(z1_app)
Error 42: Symbol Undefined _D7sqlited8Database6__initZ
z1_app.obj(z1_app)
Error 42: Symbol Undefined
_D7sqlited8Database6__ctorMFNcAyabZS7sqlited8Database
Error: linker exited with status 107814472
Is there any other native D implementation of sqlite reader?
Re: D idom for removing array elements
On Friday, 27 January 2017 at 10:20:19 UTC, albert-j wrote: I am also wondering why the standard library doesn't have convenience functions for this, e.g. like Java's removeAll? Now there's more typing than necessary for a relatively common task. That might be a good addition considering how well it can be optimized compared to a naive implementation. Of course, D version of that would accept ranges as input, not only collections.
D package for optimizing/compressing images
Are there any dub package for compressing images uploaded through web forms? Cropping/resizing may also come in handy. I want one for a vibe.d project.
Re: D idom for removing array elements
On Friday, 27 January 2017 at 08:15:56 UTC, Dukc wrote: TickDuration(28085) TickDuration(42868) TickDuration(1509) Thank you, this is very helpful. I am also wondering why the standard library doesn't have convenience functions for this, e.g. like Java's removeAll? Now there's more typing than necessary for a relatively common task.
Re: Parsing a UTF-16LE file line by line, BUG?
On Friday, 27 January 2017 at 07:02:52 UTC, Jack Applegame wrote: On Monday, 16 January 2017 at 14:47:23 UTC, Era Scarecrow wrote: static char[1024*4] buffer; //4k reusable buffer, NOT thread safe Maybe I'm wrong, but I think it's thread safe. Because static mutable non-shared variables are stored in TLS. Perhaps, but fibers or other instances of sharing the buffer wouldn't be safe/reliable, at least not for long.
Re: D idom for removing array elements
On Friday, 27 January 2017 at 08:15:56 UTC, Dukc wrote: My method is much better for large arrays I tested here. Trough, considering the size of the arrays the performance difference should be even greater, like 1000X better instead of 15X better so it's definitely not that great.
Re: D idom for removing array elements
On Thursday, 26 January 2017 at 23:10:02 UTC, albert-j wrote: Will it also work correctly and fast for arrays of custom objects? How should opCmp() be defined if objects don't have a meaningful ordering? The order of elements in the original array does not matter. Two options: either define opCmp for the custom objects, or define ordering for the sort algorithm (see std.algorithm in phobos documentation)
Re: D idom for removing array elements
On Friday, 27 January 2017 at 05:48:27 UTC, Stefan Koch wrote:
To me it looks rather slow.
please benchmark!
void main()
{ import std.stdio, std.algorithm, std.range, std.array,
std.datetime;
int[] a = [1, 2, 3, 4, 5, 6, 7, 4].cycle.take(2000).array;
int[] b = [3, 4, 6].cycle.take(2000).array;
void originalMethod()
{ auto c = a.remove!(x => b.canFind(x));
assert(c[0 .. 4] == [1, 2, 5, 7]);
}
void WilsonMethod()
{ auto c = a.filter!(x => !b.canFind(x)).array;
assert(c[0 .. 4] == [1, 2, 5, 7]);
}
void myMethod()
{ auto sortedB = sort(b.dup);
auto c = a
. filter!(i => !sortedB.contains(i))
. array
;
assert(c[0 .. 4] == [1, 2, 5, 7]);
}
auto r = benchmark!(originalMethod, WilsonMethod,
myMethod)(1);
foreach(result; r) result.writeln;
}
resulted in:
TickDuration(28085)
TickDuration(42868)
TickDuration(1509)
So, you were correct that the original method is better than
Wilsons filter. My method is much better for large arrays I
tested here. But what I think you were afraid of is that it
needlessly wastes performance by allocating a new array, and I
agree.
Also, as I said, it could be made O(n).
