Re: D for scripting?
On Friday, 20 January 2017 at 03:59:12 UTC, 岩倉 澪 wrote: I keep my scripts in ~/scripts so that I can just pull them from github and go on my merry way, with symlinks in /usr/local/bin, but rdmd doesn't -I the real directory, it does -I/usr/local/bin, and if I symlink a script.d as /usr/local/bin/script, it can't find the module. I can pass -I/home/mio/scripts on the shebang line at least... FYI dub also has a script option, which would allow you to include any dub projects in your script, e.g.: https://github.com/Abscissa/scriptlike/blob/master/USAGE.md#a-basic-script-in-d Of course then you'd have to turn the included .d files into a dub project.
Re: Learning resources for std.experimental.allocator
On Thursday, 5 January 2017 at 11:09:01 UTC, xtreak wrote: Can someone explain me the actual benefits of using this and if so any benchmarks explaining the advantage. Benefits compared to what? Compared to using the GC?
Re: Terminix Year In Review
On Monday, 2 January 2017 at 13:35:21 UTC, Mike Parker wrote: On Monday, 2 January 2017 at 00:53:04 UTC, Gerald wrote: Terminix is a GTK 3 tiling terminal emulator that has been designed following the GNOME Human Interface Guidelines. The project started just over a year ago at the start of 2016 and I thought it would be fun to look back at the project history, highlights, low-lights and goals for 2017. https://gnunn1.github.io/terminix-web/news/year-in-review/ https://www.reddit.com/r/programming/comments/5ll9j8/terminix_year_in_review_looking_back_on_a_tiling/ It was also posted to: https://www.reddit.com/r/linux/comments/5liblz/terminix_year_in_review/
Re: drepl fails because of missing lib linenoise
On Thursday, 8 December 2016 at 12:31:01 UTC, Nordlöw wrote: drepl fails to build as https://github.com/drepl/drepl/issues/58 Any ideas why? Looks like you don't have liblinenoise installed. Some basic notes on how to install on linux/macosx can be found here: https://github.com/BlackEdder/todod#linenoise
Re: Tutorial: Form upload in vibe.d
On Tuesday, 6 December 2016 at 22:28:04 UTC, aberba wrote: https://aberba.github.io/2016/form-upload-in-vibe-d/ Thanks for the tutorial! Please keep them coming.
Re: Compiling and linking libraries
On Wednesday, 16 November 2016 at 14:27:41 UTC, Darren wrote:
Hey all,
This is a very beginner problem, but not one I know how to do
on my own. Could anyone give a step-by-step guide on how to
compile libraries, and then use them in my project with DUB?
If you are happy to use dub I would just add the GL library as a
dependency to my dub.json file. Then if you call dub it will
download and compile the necessary file.
Example dub.json file:
```
{
"name": "myWindow",
"authors": [
"Darren"
],
"description": "A minimal D application.",
"copyright": "Copyright © 2016, Darren",
"dependencies": {
"derelict-gl3": "~>2.0.0-alpha.2"
}
}
```
This will build the necessary library into your library though,
so it is not the same as using a static library.
Also see the "Creating an own project" section on
https://code.dlang.org/getting_started
Re: PDF generation in D?
On Thursday, 10 November 2016 at 22:30:34 UTC, Karabuta wrote: Hello community, does anyone have on something for PDF generation in D? I may need a PDF generation library in a vibe.d project I'm working on. :) Personally I would generate markdown and use a command line tool (pandoc) to compile it to pdf. Of course ggplotd can save figures in pdf format (using cairod)
Re: problem with isnan
On Thursday, 10 November 2016 at 23:45:01 UTC, Charles Hixson wrote: you might try using std.math.isNaN instead and see what it does. It was default initialized by the class instance: classCell ... floatcurActivation; ... The this method doesn't have any mention of a few variables that are supposed to be default initialized, or which curActivation is one. std.math.isNaN should work for the default initialization (at least it does for doubles)
Re: Combining "chunkBy" and "until" algorithms
On Friday, 4 November 2016 at 08:04:12 UTC, Jacob Carlborg wrote: Currently I'm using a standard for loop iterating over the lines. I'm always looking at the current line and the next line. When the current line is the standard pattern and the next line is is not, I do a separate loop until I see a standard pattern again, collecting the lines with the non-standard pattern in an array. Could you filter [1] for the non standard pattern? Filter is lazy, so will only start looking for the next when the current one has been "handled". [1] https://dlang.org/phobos/std_algorithm_iteration.html#.filter
Re: Linux Kernel in D?
On Tuesday, 1 November 2016 at 12:12:29 UTC, Heisenberg wrote: Just an idea. Do you think it would have any advantage compared to the one that is written in C? There have been a number of projects working on this. For example: https://github.com/Vild/PowerNex
Re: Avoiding GC
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? How do I allocate / free structs / classes on the heap manually? New would be GCed memeory wouldnt it? Delete is being depreciated? thanks. There is the following: https://wiki.dlang.org/Memory_Management
Re: From Python to Dlang
On Tuesday, 18 October 2016 at 12:03:54 UTC, Alfred Newman wrote: Hello and greetings, I'm a brand new D developer coming from Python. So, can you pls guys suggest me any resource like "D for a Python Developer" or so ? BTW, I just ordered the "D Programming Language" book from AA. Cheers Another great book, available for free online: http://ddili.org/ders/d.en/index.html
Re: Tuple enhancement
On Monday, 17 October 2016 at 13:35:12 UTC, Steven Schveighoffer
wrote:
Why not something like this:
Val get(T, Val)(auto ref T item, string memberName, Val
defaultValue)
{
switch(memberName)
{
foreach(n; __traits(allMembers, T))
{
static if(is(typeof(__traits(getMember, item, n)) : Val))
case n: mixin("return item." ~ n ~ ";");
}
default:
return defaultValue;
}
}
I like the general solution, although I probably would just
expect it to fail compiling if no member is present or return
Val.init if no defaultValue is passed.
Re: [OT] Re: Mir GLAS vs Intel MKL: which is faster?
On Monday, 26 September 2016 at 11:59:57 UTC, Johan Engelen wrote: On Monday, 26 September 2016 at 11:56:39 UTC, Edwin van Leeuwen wrote: Ah, I was not aware that DMD support was dropped completely. I think that is a real shame, and it makes it _much_ less likely that I will use mir in my own projects, let alone as a dependency in another library. "_much_" :'( :'( Please don't write that to LDC devs. I love LDC, I just also tend to use DMD for testing and won't force people to use ldc over dmd if they want to use a library I build.
Re: Mir GLAS vs Intel MKL: which is faster?
On Monday, 26 September 2016 at 11:46:19 UTC, Johan Engelen wrote: On Monday, 26 September 2016 at 11:11:20 UTC, Joseph Rushton Wakeling wrote: The broader topic of what compiler features Mir GLAS uses could be the topic of an entire blog post in its own right, and might be very interesting. I guess this is my terrain. I'll think about writing that blog post :) Specific LDC features that I see in GLAS are: - __traits(targetHasFeature, ...) , see https://wiki.dlang.org/LDC-specific_language_changes#targetHasFeature - @fastmath, see https://wiki.dlang.org/LDC-specific_language_changes#.40.28ldc.attributes.fastmath.29 - Modules ldc.simd and ldc.intrinsics. - Extended allowed sizes for __vector (still very limited) To get an idea of what is different for LDC and DMD, this PR removed support for DMD: https://github.com/libmir/mir/pull/347 -Johan Ah, I was not aware that DMD support was dropped completely. I think that is a real shame, and it makes it _much_ less likely that I will use mir in my own projects, let alone as a dependency in another library.
Re: Mir GLAS vs Intel MKL: which is faster?
On Monday, 26 September 2016 at 11:36:11 UTC, Edwin van Leeuwen wrote: On Monday, 26 September 2016 at 11:32:20 UTC, Ilya Yaroshenko wrote: Updated: Mir is LLVM-Accelerated Generic Numerical Library for Science and Machine Learning. It requires LDC (LLVM D Compiler) for compilation. It doesn't really require LDC though, it just requires it to get good performance? I can still use DMD for quick testing? I would say something like: For optimal performance it should be compiled using LDC.
Re: Mir GLAS vs Intel MKL: which is faster?
On Monday, 26 September 2016 at 11:32:20 UTC, Ilya Yaroshenko wrote: Updated: Mir is LLVM-Accelerated Generic Numerical Library for Science and Machine Learning. It requires LDC (LLVM D Compiler) for compilation. It doesn't really require LDC though, it just requires it to get good performance? I can still use DMD for quick testing?
Re: polar coordinates with ggplotd
On Sunday, 18 September 2016 at 22:13:35 UTC, brocolis wrote: Found an error in ys line. Thanks. Does that mean you solved it? Currently there is no special support for other coordinate systems, but I recently added Guides for x/y coordinates which should make this relatively straightforward to implement and is next on the list. Not sure when I'll get a chunk of time to implement it though. For now you will have to convert the coordinates yourself, before plotting them.
Re: Draw math formulas with ggplotd
On Saturday, 17 September 2016 at 11:57:17 UTC, John Colvin wrote: On Saturday, 17 September 2016 at 11:45:07 UTC, Edwin van Leeuwen wrote: But I assumed he meant adding the formula onto the plot. Hah, yes, I should have read the question better. Rereading the question I am actually not sure which of us interpreted the question correctly :) Do you support embedding outside images? When I wanted nice mathematical notation generated quickly in D I have used pyd to call matplotlib's builtin math rendering (much quicker than a full latex roundtrip). You can draw onto any cairo surface, so this should be possible. You'd just need to figure out how to cast/convert a matplotlib image to a cairo image.
Re: Draw math formulas with ggplotd
On Saturday, 17 September 2016 at 11:22:04 UTC, John Colvin wrote: On Saturday, 17 September 2016 at 02:41:15 UTC, brocolis wrote: How do I draw math formulas programmatically? I want to do on screen what latex does on .pdf. And I want to draw a math formula in the image generated with ggplotd. Generate data from those formulas (I like to do this with something like iota(0, 10, 0.05).map!(x => sqrt(x) / (1 + sin(x)^^2)) and then plot that. For this part ggplotd does have a helper function: http://blackedder.github.io/ggplotd/ggplotd/stat.html#statFunction auto gg = statFunction(x => sqrt(x) / (1 + sin(x)^^2), 0.0, 10).geomLine().putIn(GGPlotD()); But I assumed he meant adding the formula onto the plot.
Re: Draw math formulas with ggplotd
On Saturday, 17 September 2016 at 09:56:09 UTC, Edwin van Leeuwen wrote: On Saturday, 17 September 2016 at 02:41:15 UTC, brocolis wrote: How do I draw math formulas programmatically? I want to do on screen what latex does on .pdf. And I want to draw a math formula in the image generated with ggplotd. You can't at the moment. Parsing latex equations is not a trivial task. When I say you can't I meant that this is not explicitly supported by ggplotd.
Re: Draw math formulas with ggplotd
On Saturday, 17 September 2016 at 02:41:15 UTC, brocolis wrote: How do I draw math formulas programmatically? I want to do on screen what latex does on .pdf. And I want to draw a math formula in the image generated with ggplotd. You can't at the moment. Parsing latex equations is not a trivial task. One possible approach would be to convert part of the equations (greek alphabet etc.) to utf and use geomLabel to "simulate" sub/super script. One caveat with this is that I am not sure how well cairo(d) supports utf.
Re: colour lib needs reviewers
On Monday, 12 September 2016 at 19:55:57 UTC, Guillaume Piolat wrote: - I've wanted a function like colorFromString many times. It's especially nice with the added #RGBA and #RRGGBBAA syntax that eg. SVG lacks. What happens when the string is invalid? Does it throw an error?
Re: colour lib needs reviewers
On Monday, 12 September 2016 at 15:06:29 UTC, Manu wrote: One of my first port-of-calls after this work would be a graph/plot library... I'd use the hell out of that. I constantly want to output data visualisations! Just for your information. ggplotd currently uses an old version of your library on the backend. I'm planning on porting it soon to the latest (dub) version.
Re: Checking all elements are unique.
On Wednesday, 31 August 2016 at 07:40:39 UTC, Dorian Haglund
wrote:
Hello,
I have an array of objects of class C which contain a id member.
I want to figure out if all the id members are unique using
functional primitives.
For example, if I have:
class C
{
int id;
}
and an array of C 'Cs';
My idea was to do:
auto ids = Cs.map!(c => c.id);
assert(equal(ids.sort().uniq(), ids.sort()));
But it doesn't compile because I can't can call sort on ids.
Any idea why ? and how to solve my initial problem, which is to
check all ids are unique.
Regards,
Dorian
Sort require an indexable array. You can convert an insertRange
to an indexable array with .array:
ids.array.sort()
You can also directly sort on id
Cs.array.sort!((a,b) => a.id < b.id);
Re: dub test
On Wednesday, 24 August 2016 at 06:32:54 UTC, Jacob Carlborg wrote: Sure, but one might not figure why a test is failing after only a single run. One might use "dub test" to run integration tests that depends on some external dependency that is causing the test to fail. I always considered dub test to be only for running unittests and not really suited for integration tests, but if that is a use case then fair enough. There are many reasons to run the test without recompiling. I might be dense, but the only other thing than integration tests that I can think of is if you use random data for testing, but that would be more correctly solved by using more random data during the unittests. Nothing is worse than tests that only sometimes fail. What is the point of recompiling when nothing has changed? I'd be all for for dub to analyse whether there are any changes, but AFAIK dub's focus is as a packaging system, not as a build system. In that case I'd prefer it to ere on the side of caution and recompile more often in case there might be a change. Maybe the key would be to replace dub's limited build system by an external build system such as reggea.
Re: dub test
On Tuesday, 23 August 2016 at 17:55:41 UTC, Andrei Alexandrescu wrote: Why does "dub test" rebuild the library? It should just re-run unittests. -- Andrei To be honest I prefer it to rebuild it. Why would you want to rerun the tests without a rebuild? It should give the same failure/success as last time.
Re: Check out blog post on vibe.d
On Monday, 22 August 2016 at 15:47:34 UTC, karabuta wrote: I made a blog post on vibe.d for people who might be into node.js and other web frameworks. Its not meant for everybody especially not for softwares engineers or hardcore coders :) Please let me know what you think. Sounds good, but where is it :)
Re: ggplotd version 1.0.0 released
On Sunday, 21 August 2016 at 12:32:11 UTC, ZombineDev wrote: I've worked extensively with data-viz UI components for WPF/SL and ASP.NET and I have to say that, after a quick glance at the readme, I really like the API of your library! Nice work! Thanks! Although I must give most of the props to ggplot2 (the R package), because it is inspired by their API :)
Re: ggplotd version 1.0.0 released
On Saturday, 20 August 2016 at 16:37:29 UTC, Edwin van Leeuwen wrote: I just wanted to announce the 1.0.0 version release of ggplotd [1]. The main addition is support for legends. Other than that the release focused on cleaning up/refactoring the code. It should still be backwards compatible though. Forgot to add what ggplotd actually is :) ggplotd is a plotting library, which uses cairo to do the actual for drawing. It supports saving as svg, pdf and png file. It also has basic support for drawing to gtk. The library design is inspired by ggplot2 for R, which in turn is based on a book called: grammar of graphics (hence gg(plot)). It supports plotting lines/points, histograms(2d) and density(2d) plots. It is written in such a way that it is easy to add your own type of plots (see the README).
ggplotd version 1.0.0 released
I just wanted to announce the 1.0.0 version release of ggplotd [1]. The main addition is support for legends. Other than that the release focused on cleaning up/refactoring the code. It should still be backwards compatible though. As always I also released a new version of plotcli (the commandline plotting tool), which now also supports legends [2]. I am afraid there is currently no prebuild plotcli version with gtk support available OSX due to a linker error with gtkd on OSX [3]. I don't have a mac, so have been unable to solve this. Any input would be appreciated :) [1] https://github.com/BlackEdder/ggplotd [2] https://github.com/BlackEdder/plotd [3] https://github.com/gtkd-developers/GtkD/issues/162
Re: Serialize/Deserialize Tuple
On Friday, 19 August 2016 at 09:55:32 UTC, Steve Biedermann wrote: I'm trying to send data over the network. On the receiving side, I need a tuple of the sent values. Is there any way to achieve this? Depends on the format the data is send in. There are a number of serialization/deserialization libraries: binary: https://github.com/atilaneves/cerealed Others: http://code.dlang.org/search?q=serial+painlessjson+cerealed
Re: Command Line Utility Library
On Tuesday, 16 August 2016 at 13:32:26 UTC, Jacob Carlborg wrote: On 2016-08-16 11:37, Seb wrote: Manual work? O_o Just open code.dlang.org and either hit CTRL-F or use the search bar (Martin added elastic search two months ago) as the packages usually have a very low PageRank. It's a bit problematic when you don't know what to search for. Not all projects have a descriptive name ;) Does it only search the description or also the README?
Re: Command Line Utility Library
On Monday, 15 August 2016 at 07:29:58 UTC, UDW wrote: Hi, I would like some options for a library, preferably json configurable, that helps with command line tool development. Doesn't have to be in D specifically. I am using: http://code.dlang.org/packages/docopt It's not really json configurable, but that shouldn't be to complex to implement yourself.
Re: Decimal/Currency Type
On Tuesday, 9 August 2016 at 10:48:50 UTC, Zane wrote: Is there such a thing build into D? If not, is there any plans to add it? It seems like this would be something needed by many applications (especially anything dealing with currency). I don't think there is anything in the standard library, but there is a dub library: https://github.com/qznc/d-money
Re: Battle-plan for CTFE
On Friday, 29 July 2016 at 11:30:20 UTC, Stefan Koch wrote: I have fresh performance statistics: Is there any improvement in memory usage?
Re: Autotesting dub packages with dmd nightly
On Monday, 18 July 2016 at 18:47:28 UTC, Jacob Carlborg wrote: On 2016-07-18 11:55, Sebastiaan Koppe wrote: Like I said I am aiming really low. On purpose. I have a wife and two kids and I need to keep the scope limited. In that case, go with something that already exists. I think Martin Nowak has some sort of automated setup for testing a limited number of dub packages against each release, but I can't find the relevant post at the moment.
Re: Using external libraries the correct way
On Sunday, 17 July 2016 at 17:52:59 UTC, solidstate1991 wrote: Up to this day, I have to use them by dragging the source into my project. When I tried to import imageformats, the compiler looks up for the file imageformats.d and fails to finish the program. I'm not using command line for compiling, I use Xamarin with mono-D instead. I tend to use dub for all my external libraries: http://code.dlang.org Not sure how that ties in with mono-D though.
Re: Docs for `Group` type
On Tuesday, 12 July 2016 at 11:40:48 UTC, Bahman Movaqar wrote: On 07/12/2016 01:01 PM, Mike Parker wrote: Do you have some sample code that shows the error? Yes. I'm working on Stockman[1] a playground to learn D. In file `etl.d`, line 110 [2], if I change the line to auto refInvoice = group[1].takeOne(); the file will not compile. I have attached the compile error to this message. Thanks, What does group.writeln; output? That should give you a good sense of what is going on.
Re: local const functions - bug ?
On Thursday, 7 July 2016 at 10:33:39 UTC, Basile B. wrote:
this compiles without error:
struct Foo
{
int i;
void bar()
{
void foo() const
{
i = 1;
}
foo;
}
}
In this case "const" seems to be a noop. Do you think it's a
bug ? Shouldn't "const" be applied, despite of foo()
inaccessibility ?
Is this related to:
https://issues.dlang.org/show_bug.cgi?id=1983
Re: daffodil, a D image processing library
On Monday, 4 July 2016 at 15:10:30 UTC, Manu wrote: On 1 July 2016 at 18:19, Edwin van Leeuwen via Digitalmars-d-announce <digitalmars-d-announce@puremagic.com> wrote: On Friday, 1 July 2016 at 08:11:37 UTC, Benjamin Schaaf wrote: On Friday, 1 July 2016 at 01:24:55 UTC, rikki cattermole wrote: On 01/07/2016 9:35 AM, Benjamin Schaaf wrote: Doesn't use allocators or Manu's color work, yup yup not interested. In terms of std.experimental.color, one of the things I focused on was extensibility. Also, the only way currently to use Manu's color work is to install his phobos branch. The dub package will throw unittest errors and loads of deprecation warnings. Really? Nobody ever mentioned that before. I don't use dub, so I didn't notice... but I thought the code there was up to date...? Maybe I am confused. I am talking about the code/package here: https://github.com/TurkeyMan/color which hasn't seen an update since november. Relevant issue: https://github.com/TurkeyMan/color/issues/5 I had a look at the unittest, but couldn't immediately figure out why it wasn't working, so didn't look further into it.
Re: daffodil, a D image processing library
On Friday, 1 July 2016 at 08:11:37 UTC, Benjamin Schaaf wrote: On Friday, 1 July 2016 at 01:24:55 UTC, rikki cattermole wrote: On 01/07/2016 9:35 AM, Benjamin Schaaf wrote: Doesn't use allocators or Manu's color work, yup yup not interested. In terms of std.experimental.color, one of the things I focused on was extensibility. Also, the only way currently to use Manu's color work is to install his phobos branch. The dub package will throw unittest errors and loads of deprecation warnings.
Re: Garbage Collector
On Wednesday, 15 June 2016 at 17:03:21 UTC, Konstantin wrote: On Wednesday, 15 June 2016 at 13:56:09 UTC, Jack Stouffer wrote: Has anyone thought about taking GC from .NET and reusing it in D? Two words: write barriers. What about them? You mean not all D’s target platforms support them? I think he meant that the .NET GC (and most GC designs) rely on write barriers, but D does not have write barriers, since D is meant to be a proper systems language.
Re: Button: A fast, correct, and elegantly simple build system.
On Wednesday, 15 June 2016 at 15:39:47 UTC, Andrei Alexandrescu wrote: On 06/15/2016 08:05 AM, John Colvin wrote: On Wednesday, 15 June 2016 at 11:47:00 UTC, Walter Bright wrote: On 6/15/2016 4:07 AM, Edwin van Leeuwen wrote: How about using reggae? https://github.com/atilaneves/phobos/blob/reggae/reggaefile.d I haven't studied either. If you do study that reggae file, remember that it's a deliberate transliteration of the makefile and therefore is a lot more verbose than it *could* be if done from a clean slate or as a proper translation. IIRC it was done to show that reggae could do literally everything the makefile does, in the same way. Does it do -j? -- Andrei It can work with multiple backends (make/tup/ninja), which all support -j. There is also a binary backend (creates an executable), not sure if that supports -j natively.
Re: Button: A fast, correct, and elegantly simple build system.
On Monday, 13 June 2016 at 00:27:47 UTC, Walter Bright wrote: On 5/30/2016 12:16 PM, Jason White wrote: Here is an example build description for DMD: https://github.com/jasonwhite/dmd/blob/button/src/BUILD.lua I'd say that's a lot easier to read than this crusty thing: https://github.com/dlang/dmd/blob/master/src/posix.mak Yes, the syntax looks nice. How about using reggae? https://github.com/atilaneves/phobos/blob/reggae/reggaefile.d
Re: Beta release DUB 1.0.0-beta.1
On Tuesday, 7 June 2016 at 09:54:19 UTC, Sönke Ludwig wrote: DUB 1.0.0 is nearing completion. The new feature over 0.9.25 is support for single-file packages, which can be used to write shebang-style scripts on Posix systems: #!/usr/bin/env dub /++ dub.sdl: name "colortest" dependency "color" version="~>0.0.3" +/ I love that as a feature! Thanks for adding that.
Re: mir.random - my GSoC project
On Thursday, 2 June 2016 at 10:56:36 UTC, Martin Nowak wrote: On 04/23/2016 04:17 PM, Seb wrote: This project is about adding non-uniform random generators to mir and hopefully eventually to Phobos. I just happen to need a gaussian random number generator right now. Is there already some WIP code, or would you have an intermediate recommendation? I tend to use rNorm from dstats: https://github.com/dsimcha/dstats/blob/master/source/dstats/random.d#L266
Re: Trying to get type and name at compile time
On Tuesday, 24 May 2016 at 18:44:45 UTC, ag0aep6g wrote: Seems to be a problem in ApplyLeft: import std.meta: AliasSeq, ApplyLeft; alias addType(T, string name) = AliasSeq!(T, name); alias addTypeInt = ApplyLeft!(addType, int); alias FullyInstantiated = addTypeInt!"foo"; Fails with: "std/meta.d(1114): Error: cannot interpret int at compile time". I've filed an issue: https://issues.dlang.org/show_bug.cgi?id=16070 Thanks! I've worked around it for now with some recursion :) Using `is(...)` with an AliasSeq of only types is ok. But you can't use it when there's a non-type in the sequence. That makes sense. Thanks for the help, Edwin
Re: Trying to get type and name at compile time
On Tuesday, 24 May 2016 at 15:09:43 UTC, Adam D. Ruppe wrote:
On Tuesday, 24 May 2016 at 15:01:33 UTC, Edwin van Leeuwen
wrote:
// I expected AliasSeq!(double,"x")???
pragma(msg,test); // tuple((double), "x")
What Phobos calls AliasSeq is called tuple inside the compiler.
They are the same thing, just different names.
That's what I assumed at first.. So why does the following fail
with: cannot interpret double at compile time? I assumed
staticMap would automatically flatten the resulting AliasSeqs.
```
import std.meta : AliasSeq, ApplyLeft, staticMap;
struct Point { double x; double y; }
template addType(T,alias name)
{
alias addType = AliasSeq!( typeof(__traits(getMember, Point,
name)),
name );
}
alias test3 = addType!( Point, "x" );
// I expected AliasSeq!(double,"x")???
pragma(msg,test3); // tuple((double), "x")
//static assert(is(test == AliasSeq!(double,"x")));
alias ts = AliasSeq!("x","y");
alias addTypeP = ApplyLeft!(addType,Point);
alias mapped = staticMap!(addTypeP,ts);
pragma(msg,mapped);
void main() {
}
```
Looking at it now, I guess it is because staticMap does not work
with alias values, only with actual type lists. Is that correct?
Any ideas on how to do this?
static assert(is(test == AliasSeq!(double,"x")));
AliasSeq is not comparable as a type. You can test the
individual pieces of it (`is(test[0] == double) && test[1] ==
"x"`) or wrap it in a struct or something.
I thought so, but a lot of the documentation does seem to compare
it (see the example here):
https://dlang.org/library/std/meta/static_map.html
Trying to get type and name at compile time
Hi all,
I am trying to get the type and name of a field at compile time,
but can't get the following to work. Anyone any idea of why test
is not of the type AliasSeq!(double, "x")?
```
import std.meta : AliasSeq;
struct Point { double x; double y; }
alias test = AliasSeq!(
typeof(__traits(getMember, Point, "x")),
"x"
);
// I expected AliasSeq!(double,"x")???
pragma(msg,test); // tuple((double), "x")
static assert(is(test == AliasSeq!(double,"x")));
void main() {}
```
Cheers, Edwin
Re: matrix library
On Monday, 23 May 2016 at 23:08:46 UTC, Vlad Levenfeld wrote: Now I am thinking that the best way to orthogonalize (sorry) my efforts with respect to mir and scid.linalg is to use them as backend drivers, maintain this wrapper for the crowd that isn't as familiar with blas/lapack, or wants to write slightly more concise top-level code, and forward the relevant bug reports and pull requests to mir and scid. You might be interested in joining the gitter channel where the mir developers hang out: https://gitter.im/libmir/public
Re: matrix library
On Monday, 23 May 2016 at 20:27:54 UTC, Vlad Levenfeld wrote: On Monday, 23 May 2016 at 20:11:22 UTC, Vlad Levenfeld wrote: ... On first glance it looks like https://github.com/DlangScience/scid/blob/master/source/scid/matrix.d has most of what my matrix implementation is missing. Not sure how to put them together yet. There is also mir, which is working towards being a full replacement for blas: https://github.com/libmir/mir It is still under development, but I think the goal is to become the ultimate matrix library :)
Re: static member and/or @property ?
On Thursday, 19 May 2016 at 15:12:44 UTC, Edwin van Leeuwen wrote: On Thursday, 19 May 2016 at 15:04:00 UTC, chmike wrote: The only viable solution I found so far is by using distinct member names. In the interface we define name as a property, and in the class we define the static member with another name. Is it possible to avoid the different names ? Can you use identifier!(typeof(this)) or something along those lines. I am not sure how it behaves with inheritance. https://dlang.org/spec/traits.html#identifier Sorry I meant __traits(identifier, typeof(this)).
Re: static member and/or @property ?
On Thursday, 19 May 2016 at 15:04:00 UTC, chmike wrote: The only viable solution I found so far is by using distinct member names. In the interface we define name as a property, and in the class we define the static member with another name. Is it possible to avoid the different names ? Can you use identifier!(typeof(this)) or something along those lines. I am not sure how it behaves with inheritance. https://dlang.org/spec/traits.html#identifier
Re: Compile Tango for DMD2 - Any instructions how to do it?
On Wednesday, 18 May 2016 at 16:37:48 UTC, TheDGuy wrote: On Wednesday, 18 May 2016 at 16:13:35 UTC, Seb wrote: May I ask why you need to get tango working? It has been deprecated a long time ago and phobos (the standard library) or alternatively other packages on dub have a look of features :) Okay, it looks like 'onyx' is a library which handles serial communication in D. So tried to create a new project with DUB and add onyx as dependency but there are still some errors: http://pastebin.com/4eRBt6XX Any idea what i do wrong? The onyx README seems to suggest it only works for POSIX. Did you try serial-port by any chance: http://code.dlang.org/packages/serial-port That does mention Windows as supported. It is quite old though, the latest github activity is from a year ago.
ggplotd v0.9: Added geomDensity and geomDensity2d support. Documentation improvements
I’d like to announce a new release of the ggplotd plotting library. https://github.com/BlackEdder/ggplotd Main changes are: User visible change: - geomDensity and geomDensity2D (kernel smoothed hist and hist2d) - Browseable api documentation using harbored-mod - Updates to documentation - Some deprecations due to moving/renaming - mergeRange moved to ggplotd.range - geomHist3D renamed to geomHist2D Other changes: - Addition of ggplotd.stat module - Split some geom functions into separate geom and stat part - Many refactors Plotcli: https://github.com/BlackEdder/plotd A new version of plotcli has also been released, which depends on the new ggplotd version. As a result plotcli can now also create density and density2d plots (which are basically smoothed histograms).
Re: PropertyType
On Tuesday, 17 May 2016 at 14:24:09 UTC, Steven Schveighoffer
wrote:
I have this little helper in my iopipe library:
template PropertyType(alias x)
{
static if(is(typeof(x) == function))
alias PropertyType = typeof(x());
else
alias PropertyType = typeof(x);
}
FYI: In painlesstraits we use a different approach, where we test
whether it is a function (with isSomeFunction) and then test for
the property attribute:
https://github.com/msoucy/painlesstraits/blob/master/source/painlesstraits.d#L173
```
static if (isSomeFunction!(T))
{
return (functionAttributes!(T) &
FunctionAttribute.property);
} else
return false;
```
Re: The D language online tour - tour.dlang.org
On Monday, 16 May 2016 at 17:32:06 UTC, André wrote: Hi, after another round of polishing, bug fixing, very useful user contributions and suggestions, I'd like to present the new home of the D language online tour: http://tour.dlang.org/ Thank you very much to the D foundation for hosting this service! If you would like to report errors or have suggestions, please use GitHub: https://github.com/stonemaster/dlang-tour Thanks & regards, André Nice work. Will this be mentioned/linked too in the Learn section of the dlang.org?
Re: static import (v2.071.0)
On Wednesday, 11 May 2016 at 14:24:03 UTC, Chris wrote: I was wondering if `static import std.file;` `if (exists(file))` will only import `std.file.exists` or the whole lot of `std.file`? I want to find out what the best strategy for imports is now. I tend to do specified imports, although (AFAIK) it doesn't make a difference for the imported code: private import std.file : exists; if (exists(file))
Re: ggplotd - curve colour
On Monday, 9 May 2016 at 02:29:47 UTC, brocolis wrote:
Is this correct usage?
auto gg = GGPlotD().put( geomLine( Aes!(typeof(xs), "x",
typeof(ysfit), "y", string, "colour")( xs, ysfit, "red") ) );
The output is a blank png file.
Full source:
import ggplotd.ggplotd;
import ggplotd.geom;
import ggplotd.aes;
import ggplotd.axes;
void main()
{
import std.array : array;
import std.algorithm : map;
import std.range : iota;
import ggplotd.colour;
auto f = (double x) { return x; };
auto xs = iota(-5, 5, 0.1 ).array;
auto ysfit = xs.map!((x) => f(x)).array;
auto gg = GGPlotD().put( geomLine( Aes!(typeof(xs), "x",
typeof(ysfit), "y", string, "colour")( xs, ysfit, "red") ) );
gg.put( xaxisOffset( 0) ).put( yaxisOffset( 0) );
gg.save( "axes.png", 500, 300 );
}
The problem there is that colour also needs to be an InputRange.
This is so that different points can have a different colours
associated with it, which is particularly useful if you want to
plot some data and have different types of data plotted as
different colours.
In your example you can either do:
```
auto colour = "red".repeat( xs.length );
auto gg = GGPlotD().put( geomLine( Aes!(typeof(xs), "x",
typeof(ysfit), "y", typeof(colour), "colour")( xs, ysfit,
colour) ) );
```
Or use the mergeRange function mentioned before, which will
automatically repeat if one argument is a single element.
```
auto aes = Tuple!( string, "colour" )( "red" ).mergeRange(
Aes!(typeof(xs), "x",
typeof(ysfit), "y" )( xs, ysfit ) );
```
Re: ggplotd - curve colour
On Sunday, 8 May 2016 at 01:50:38 UTC, brocolis wrote:
How do I set the color of a curve with ggplotd?
Thanks.
Also see the below example on how to merge Colour with an
existing range of points using mergeRange:
(Copied from http://blackedder.github.io/ggplotd/stat.html)
void main()
{
/// http://blackedder.github.io/ggplotd/images/function.png
import std.random : uniform;
import std.typecons : Tuple;
import ggplotd.stat : statFunction;
import ggplotd.ggplotd : GGPlotD;
import ggplotd.geom : geomLine, geomPoint;
import ggplotd.aes : mergeRange;
auto f = (double x) { return x / (1 + x); };
auto aes = statFunction(f, 0.0, 10);
auto gg = GGPlotD().put(geomLine(aes));
// Generate some noisy points
auto f2 = (double x) { return x / (1 + x) * uniform(0.75,
1.25); };
auto aes2 = f2.statFunction(0.0, 10, 25);
// Show points in different colour
auto withColour = Tuple!(string,
"colour")("aquamarine").mergeRange(aes2);
gg = gg.put(withColour.geomPoint);
gg.save("function.png");
}
Re: ggplotd - curve colour
On Sunday, 8 May 2016 at 01:50:38 UTC, brocolis wrote: How do I set the color of a curve with ggplotd? Thanks. You can set colours by name: https://github.com/BlackEdder/ggplotd/blob/master/source/ggplotd/colour.d#L20 Alternatively you can pass through the RGB value (see the link above for the specification). Finally if you have multiple curves and don't want to specify specific colours you can just give them a different identifier (e.g. different double/int value (any type should do)) and it will chose the colours according to the colourgradient used. There is an example on how to specify your own gradient in the hist3D.svg example: http://blackedder.github.io/ggplotd/ggplotd.html
Re: Computer Vision Library in D
On Thursday, 28 April 2016 at 11:32:25 UTC, Michael wrote: And I would also like to see some more scientific libraries make it into D. Though I understand that including it in the standard library can cause issues, it would be nice to at least get some Linear Algebra libraries in experimental or over with the rest of the science libraries. As I understand it that is part of the goal of mir: https://code.dlang.org/packages/mir Not sure if you were aware, but there is also a group with the aim to promote scientific dlang work: https://gitter.im/DlangScience/public
Re: DUB and pragma lib - OSX
On Wednesday, 20 April 2016 at 05:53:28 UTC, Joel wrote: How do I get this C stuff working with DUB? Mind posting your dub configuration file?
Re: JSONValue floating and 42
On Tuesday, 19 April 2016 at 13:44:08 UTC, Andre wrote: -> I need to analyze every value whether it is a floating or an integer? This is the correct option. Something like: double f; if (j["value"].type == JSON_TYPE.INTEGER) f = j["value"].integer.to!float; else f = j["value"].floating; There are also a number of libraries available that make dealing with json a bit easier: code.dlang.org/search?q=json
Re: Command line utilities for tab-separated value files
On Tuesday, 12 April 2016 at 07:17:05 UTC, Jon D wrote: I'd certainly like to make it available via dub, but I wasn't sure how to set it up. There are two issues. One is that the package builds multiple executables, which dub doesn't seem to support easily. More problematic is that quite a bit of the test suite is run against the executables, which I could automate using make, but didn't see how to do it with dub. If there are suggestions for setting this up in dub that'd be great. An example project doing something similar would be really helpful. Dub is indeed not ideal for building multiple executables. You can either use subConfigurations or subPackages. In your case I would probably go the subPackages route, with the root dub file depending on all the executables. Never done that before though, so not exactly sure if that would work. If it works though then I'd think dub test in the root would run the tests for each subPackage.
Re: Official dub packages for Debian and Ubuntu
On Monday, 11 April 2016 at 14:21:46 UTC, Matthias Klumpp wrote: And porting Python code to D was incredibly easy. I'll likely blog about my experience with D). That would be great. Do you have a link to your blog (and its rss feed)? As part of that work, the dub package an build management system is now available in Debian, and I will ensure it works well. Nice, that will make it a lot easier, for people that are not using D, to install D programs/packages
Re: simple range question
On Friday, 8 April 2016 at 18:27:59 UTC, Laeeth Isharc wrote: suppose I have a forward or random access range. what's the best way to compare each element with the element 4 elements prior to that element? I could map each element to a tuple of the element and the element 4 bars previously and do it that way. any neater way ? I'd do it like this, but I guess that is what you mean with mapping it to a tuple: zip( r, r[4..$] ).map!((t) => t[0] == t[1]);
Re: is std.algorithm.joiner lazy?
On Thursday, 7 April 2016 at 09:55:56 UTC, Puming wrote:
When compiled, I get the error:
Error: open path skips field __caches_field_0
source/app.d(19, 36): Error: template instance
std.algorithm.iteration.cache!(MapResult!(__lambda1, int[]))
error instantiating
That seems like a bug to me and you might want to submit it to
the bug tracker. Even converting it to an array first does not
seem to work:
import std.stdio : writeln;
import std.algorithm : map, cache, joiner;
import std.array : array;
auto read(int a) {
return [0, a]; // second level
}
auto mkarray(int a) {
return [-a, a].map!(x=>read(x)).cache.joiner; // to avoid
calling read twice
}
void main() {
auto xs = [1,2 ,3, 4];
auto r = xs.map!(x=>mkarray(x)).array;
// Both lines below should be equal, but second does not compile
[[0, -1, 0, 1], [0, -2, 0, 2], [0, -3, 0, 3], [0, -4, 0,
4]].cache.joiner.writeln;
r.cache.joiner.writeln;
}
Above results in following error:
/opt/compilers/dmd2/include/std/algorithm/iteration.d(326):
Error: one path skips field __caches_field_0
/d617/f62.d(19): Error: template instance
std.algorithm.iteration.cache!(Result[]) error instantiating
Re: is std.algorithm.joiner lazy?
On Thursday, 7 April 2016 at 08:17:38 UTC, Puming wrote: On Thursday, 7 April 2016 at 08:07:12 UTC, Edwin van Leeuwen wrote: OK. Even if it consumes the first two elements, then why does it have to consume them AGAIN when actually used? If the function mkarray has side effects, it could lead to problems. After some testing it seems to get each element twice, calls front on the MapResult twice, on each element. The first two mkarray are both for first element, the second two for the second. You can solve this by caching the front call with: xs.map!(x=>mkarray(x)).cache.joiner;
Re: is std.algorithm.joiner lazy?
On Thursday, 7 April 2016 at 07:07:40 UTC, Puming wrote:
Hi:
when I use map with joiner, I found that function in map are
called. In the document it says joiner is lazy, so why is the
function called?
say:
int[] mkarray(int a) {
writeln("mkarray called!");
return [a * 2]; // just for test
}
void main() {
auto xs = [1, 2];
auto r = xs.map!(x=>mkarray(x)).joiner;
}
running this will get the output:
mkarray called!
mkarray called!
I suppose joiner does not consume?
when I actually consume the result by writlen, I get more
output:
mkarray called!
mkarray called!
[2mkarray called!
mkarray called!
, 4]
I don't understand
Apparently it works processing the first two elements at
creation. All the other elements will be processed lazily.
Even when a range is lazy the algorithm still often has to
"consume" one or two starting elements, just to set initial
conditions. It does surprise me that joiner needs to process the
first two, would have to look at the implementation why.
Re: how to parse a string into a phobos datatype with additional logic
On Thursday, 7 April 2016 at 07:45:06 UTC, yawniek wrote: what is the way one is supposed to parse e.g. a double of unixtime (as delived by nginx logs) into a SysTime? currently i'm creating a wrapper struct around SysTime with alias this as: https://gist.github.com/yannick/6caf5a5184beea0c24f35d9d4a4c7783 really ugly imho. is there a better way to do this? You can try this library: https://code.dlang.org/packages/dateparser
Re: Read only delegate
On Monday, 4 April 2016 at 11:39:55 UTC, Kagamin wrote: On Monday, 4 April 2016 at 11:32:23 UTC, Rene Zwanenburg wrote: https://issues.dlang.org/show_bug.cgi?id=1983 Bug 1983 is about usage of delegates after creation, restrictions during creation are enforced. AIU, OP wants to have const check during creation. I think the underlying issue is the same. The problem seems to be that: Unfortunately, there is no way to declare a const delegate (by which I mean, a delegate whose context pointer is typed const). I actually discovered the problem, due to the hole it leaves in the const system, where I got different results calling a const method multiple times. The const method in question called a delegate that changed its context pointer, resulting in changes during calls.
Re: Read only delegate
On Monday, 4 April 2016 at 11:32:23 UTC, Rene Zwanenburg wrote: On Monday, 4 April 2016 at 08:10:10 UTC, Edwin van Leeuwen wrote: Is there a way to make sure a delegate only reads state, without changing it? I tried annotating the delegate as const, but that does not seem to work. ``` Yeah this is a nasty old issue. The underlying problem is that a delegate's function and context pointers are completely untyped. https://issues.dlang.org/show_bug.cgi?id=1983 Thanks for the reference, hopefully this will be resolved at some point :)
Re: Read only delegate
On Monday, 4 April 2016 at 08:10:10 UTC, Edwin van Leeuwen wrote:
Is there a way to make sure a delegate only reads state,
without changing it? I tried annotating the delegate as const,
but that does not seem to work.
Note that annotating with pure also doesn't help. As a result we
can have a pure delegate that returns different results every
time it is called.
```D
void main()
{
import std.stdio : writeln;
auto r = [0,1,2,3];
auto f = delegate() const pure
{
import std.array : front, popFront;
r.popFront;
return r.front;
};
r.writeln; // [0,1,2,3]
auto f1 = f();
r.writeln; // [1,2,3]
assert( f() == f1 ); // Throws
}
```
Read only delegate
Is there a way to make sure a delegate only reads state, without
changing it? I tried annotating the delegate as const, but that
does not seem to work.
```D
void main()
{
import std.stdio : writeln;
auto r = [0,1,2,3];
auto f = delegate() const // Compiles even though we are
changing r
{
import std.array : popFront;
r.popFront;
};
r.writeln; // [0,1,2,3]
f();
r.writeln; // [1,2,3]
}
```
Re: infer type argument in classe constructor?
On Tuesday, 29 March 2016 at 10:13:28 UTC, Puming wrote:
Hi,
I'm writing a generic class：
```d
struct Message { ... }
class Decoder(MsgSrc) {
}
```
When using it, I'd have to include the type of its argument:
```
void main() {
Message[] src = ...;
auto decoder = new Decoder!(Message[])(src);
...
}
```
Can it be inferred so that I only need to write?
```d
auto decoder = new Decoder(src); // you can infer the type from
src.
```
You can't directly. This is (AFAIK) because this()() can also be
templated, making it impossible to just derive. The common way in
D to deal with this/work around it is to create a helper function
that can infer it:
```D
auto decoder(T)(T src)
{
return new Decoder!T(src);
}
auto dec = decoder(src)
```
This pattern is widely used in phobos (e.g. tuple and Tuple)
Re: Usage of custom class with JSONValue
On Thursday, 24 March 2016 at 11:39:13 UTC, arturg wrote: isnt alias this supposed to do this implicitly? convert this auto jsValue = JSONValue(new MyClass()); into this auto jsValue = JSONValue((new MyClass())._data); Good point, I did not catch that. That indeed should work and seems to be a bug. Does it work if _data is a base type (string or int, etc..)
Re: Usage of custom class with JSONValue
On Thursday, 24 March 2016 at 08:15:12 UTC, Andre wrote:
Hi,
I have a class which has already an alias this to a string
array,
so I can use it in a foreach loop.
class MyClass
{
string[] _data;
alias _data this;
// ...
}
void main()
{
import std.json;
auto jsValue = JSONValue(new MyClass());
}
For some generic code I need an implicit conversion of MyClass
so I can
use it for a JSONValue. For the coding above I receive a
compiler error:
static assert "unable to convert type "MyClass" to json"
JSONValue only works with the build in types, not with user
defined types. Either you define a specific function for the
class that returns a JSONValue. Easiest way to do that would be
to build an associative array with strings as keys with the
names, and JSONValues as values and turn that into JSONValue,
i.e. (untested):
class MyClass
{
string[] _data;
alias _data this;
// ...
JSONValue toJSON()
{
JSONValue[string] aa;
JSONValue[] dataJSON = _data.map!((a) => JSONValue(a)).array;
aa["data"] = JSONValue(dataJSON);
return JSONValue(aa);
}
}
Alternatively there are multiple serialization libraries that
will allow you to turn any user defined type from and to
JSONValues.
https://code.dlang.org/packages/painlessjson
https://code.dlang.org/packages/jsonizer
Cheers, Edwin
Re: iota result as member variable
On Thursday, 24 March 2016 at 06:54:25 UTC, Alex wrote:
Hi everybody,
doing some optimization on my code, I faced some strange
question:
how to save a iota result in a class member?
Say I have
class A
{
??? member;
auto testIter4()
{
return iota(0,5);
}
}
void main()
{
A a = new A();
a.member = testIter4();
}
how would I declare the member?
Yeah this is one of the downsides of voldermort types. In these
cases typeof and ReturnType are your friend. It often takes me a
couple of tries to get it right, but the following seems to work:
import std.traits : ReturnType;
import std.range : iota;
class A
{
ReturnType!(A.testIter4) member;
auto testIter4()
{
return iota(0,5);
}
}
void main()
{
A a = new A();
a.member = a.testIter4();
}
Re: Some crazy ideas from a high level perspective
On Tuesday, 22 March 2016 at 15:50:15 UTC, Basile B. wrote: On Tuesday, 22 March 2016 at 15:33:04 UTC, Edwin van Leeuwen wrote: On Tuesday, 22 March 2016 at 15:19:10 UTC, rikki cattermole wrote: Idea 1: Sigh I do wish the author of gl3n had given permission for relicense for Phobos. Would do what you want. Idea 3: My goal is get windowing/image library into Phobos. Now that is not a UI toolkit but you can atleast get a window up and show an image like a graph. Kinda everything you want. Any tips on how easy it will be to plot a cairo surface to a window ? Very easy. - wrap a context in a Canvas with the methods for drawing. - BLIT the cairo surface. Thanks! It also works with simple bitmaps, so image proceduraly rendered. Actually I've started to work on this at the end of 2015. (https://github.com/BBasile/kheops/blob/master/src/kheops/bitmap.d#L396) That looks interesting. Would you say kheops is stable enough to be relied upon by other projects? Any plans to make it into a dub package? Since kheops is vector based it would be even nicer to be able to convert a cairo svg/pdf surface to kheops. While it was planned to make a native D UI, using it to plot 2D data would require very few work. There's also a OO wrapper called cairoD or something like that which is for sure very easy to use to render bitmap proceduraly. cairoD is indeed what ggplotd uses to produce the plot. And saving svg/png/pdf to disk is indeed very easy with cairo.
Re: Some crazy ideas from a high level perspective
On Tuesday, 22 March 2016 at 15:19:10 UTC, rikki cattermole wrote: Idea 1: Sigh I do wish the author of gl3n had given permission for relicense for Phobos. Would do what you want. Idea 3: My goal is get windowing/image library into Phobos. Now that is not a UI toolkit but you can atleast get a window up and show an image like a graph. Kinda everything you want. Any tips on how easy it will be to plot a cairo surface to a window? ggplotd currently relies on gtkd for that, but would be great if there is a D based solution. I'm especially interested in plotting image of the below type in a window: CAIRO_FORMAT_ARGB32[1] each pixel is a 32-bit quantity, with alpha in the upper 8 bits, then red, then green, then blue. The 32-bit quantities are stored native-endian. Pre-multiplied alpha is used. (That is, 50% transparent red is 0x8080, not 0x80ff.) [1] cairographics.org/manual-1.2.0/cairo-Image-Surfaces.html
Re: Something wrong with GC
On Tuesday, 22 March 2016 at 13:46:41 UTC, stunaep wrote:
public class Example2 {
private int one;
private int two;
public this(int one, int two) {
this.one = one;
this.two = two;
}
}
in a tree map and list of some sort. Neither of the above work
whether they are classes or structs and it's starting to become
quite bothersome...
Is there a particular reason why you don't want to use the
standard ranges?
public class Example2 {
private int one;
private int two;
public this(int one, int two) {
this.one = one;
this.two = two;
}
}
void main()
{
auto myExamplesList = [ new Example2( 6,3 ), new Example2(7,5) ];
// Note that if you do a lot of appending then using
Appender is more performant than ~=
myExamplesList ~= new Example2(9,1);
}
For trees there is also redBlackTree
Re: Gdmd compiling error
On Wednesday, 16 March 2016 at 12:17:42 UTC, Orkhan wrote: On Tuesday, 15 March 2016 at 18:26:48 UTC, Ali Çehreli wrote: I don't know where from shpuld I get help. Thanks. Is the xcomm library available somewhere, maybe if we had a link to the original documentation we could help.
Re: Obtaining argument names in (variadic) functions
On Wednesday, 16 March 2016 at 20:53:42 UTC, JR wrote:
void printVars(Args...)()
if (Args.length > 0)
{
import std.stdio : writefln;
foreach (i, arg; Args) {
writefln("%s\t%s:\t%s", typeof(Args[i]).stringof,
Args[i].stringof, arg);
}
}
void main() {
int abc = 3;
string def = "58";
float ghi = 3.14f;
double jkl = 3.14;
printVars!(abc,def,ghi,jkl)();
}
Interesting, any idea if it is possible to do assignment within
template.. Either:
printVars!(int abc=5,string def="58")();
or something like
printVars!("abc","def",ghi)(5,"58");
Re: Obtaining argument names in (variadic) functions
On Thursday, 17 March 2016 at 13:53:00 UTC, JR wrote:
Interesting, any idea if it is possible to do assignment
within template.. Either:
printVars!(int abc=5,string def="58")();
or something like
printVars!("abc","def",ghi)(5,"58");
What would the use-cases for those be?
I don't think the first is valid grammar, and I'm not sure what
you want the second to do. Resolve symbols by string literals
of their names? That might need a string mixin as they wouldn't
be in scope when in the called template function, but I've
never tried it.
Both use cases are when you want a named parameter, without
having to assign it first. I know the first is not valid grammar,
was just wondering if you might be smarter than me and see a way
to make it valid :)
Second one is another possible alternative that I have been
thinking about.
Basically, say I want to have the named (optional) parameters x
and y. In your initial example I would be required to do:
```
int x = 1;
string y = "2";
doSomethingWithNamedPars!(x,y)();
```
I just hoped to shorten that to a one liner similar to:
```
doSomethingWithNamedPars!(x=1,y="2")();
```
or alternatively
```
doSomethingWithNamedPars!("x","y")(1,"2");
```
(where doSomethingWithNamedPars's behaviour depends on which
named parameters it is passed)
Just as a reference, my current approach (in ggplotd) is with
named tuples, but that is slightly more verbose than I had hoped:
```
doSomethingWithNamedPars( Tuple!(int, "x", string, "y")( 1, 2 ) );
```
Re: dmd-built dmd is faster that ldc-built dmd or gdc-built dmd?
On Friday, 11 March 2016 at 14:46:59 UTC, Vladimir Panteleev wrote: Thanks :) After changing that to version(all), LDC is faster now. Doesn't build with GDC though (multiple definitions)... How much faster is LDC?
Re: How to sort a range
On Wednesday, 9 March 2016 at 15:39:55 UTC, rcorre wrote: On Wednesday, 9 March 2016 at 14:28:11 UTC, cym13 wrote: Still curious as to why it fails; maybe the range is getting copied at some point? I guess I need to step through it. I did try different SwapStrategies with no luck. Since you are adapting phobos anyway you could try commenting out the assert and see what the result of the sort is. That might give you some clue: //assert(isSorted!lessFun(r), "Failed to sort range of type " ~ Range.stringof); Also I notice the line numbering is different in my sorted.d file. Did you test the latest version of dmd/phobos?
Re: How to sort a range
On Wednesday, 9 March 2016 at 13:04:31 UTC, rcorre wrote: On Wednesday, 9 March 2016 at 12:31:18 UTC, Edwin van Leeuwen wrote: On Wednesday, 9 March 2016 at 12:21:55 UTC, rcorre wrote: If you are looking for a lazy uniq that works on non sorted ranges, I implemented one not to long ago: http://github.com/BlackEdder/ggplotd/blob/master/source/ggplotd/range.d That sounds like the kind of thing I was looking for. I'll take a look, thanks! Well that one does allocate, because it keeps track of which values have already been seen. Yup, just noticed that >.< Of course it only allocates when the actual result is used, so this will probably be more efficient if you only need a small number of unique results or need to keep the unsorted range around/intact. Sorting without allocating and then using uniq should indeed be more efficient in other cases. Did you try different SwapStrategy values in your original?
Re: How to sort a range
On Wednesday, 9 March 2016 at 12:21:55 UTC, rcorre wrote: If you are looking for a lazy uniq that works on non sorted ranges, I implemented one not to long ago: http://github.com/BlackEdder/ggplotd/blob/master/source/ggplotd/range.d That sounds like the kind of thing I was looking for. I'll take a look, thanks! Well that one does allocate, because it keeps track of which values have already been seen.
Re: How to sort a range
On Wednesday, 9 March 2016 at 03:05:52 UTC, rcorre wrote: I was in a situation where I wanted to remove duplicates from an OnlyResult. To do this with uniq, I needed to sort it. OnlyResult doesn't satisfy the template constraints of sort, but this seems easy enough to fix. I made front, back, and opIndex return by ref. With this, the following compiles: assert(only(3,1,2).sort.equal(only(1,2,3))); However, it fails with: core.exception.AssertError@std/algorithm/sorting.d(1052): Failed to sort range of type OnlyResult!(int, 3LU) So, if you have a range for which sort compiles, what does it take to make sorting actually work? For reference, my two attempts were: https://github.com/rcorre/phobos/commit/d89b3cfab7a0938e178a506b4ceb8faae6ecbfe2 https://github.com/rcorre/phobos/commit/512d9b8db6f311db6a9b6ccb077a691cec66ce70 I'm not sure why your fix didn't work, but generally I work around this by converting the OnlyResult into an array: import std.array : array; assert(only(3,1,2).array.sort.equal(only(1,2,3))); If you are looking for a lazy uniq that works on non sorted ranges, I implemented one not to long ago: http://github.com/BlackEdder/ggplotd/blob/master/source/ggplotd/range.d
Re: Named arguments via struct initialization in functions
On Wednesday, 9 March 2016 at 07:30:31 UTC, Edwin van Leeuwen wrote: I also added a merge function that will return a tuple containing merged named tuples: Tuple!(double,"x",string,"colour")(-1, "black").merge(Tuple!(double,"x")(0.0)) returns: Tuple!(double,"x",string,"colour")(0, "black"); Quick clarification. The merge function is used to merge the passed tuple, with the default values needed in the function. This way we don't have to worry about missing values.
Re: Named arguments via struct initialization in functions
On Sunday, 6 March 2016 at 17:35:38 UTC, Seb wrote:
Hey all,
Using structs is not ideal, because one can't require
parameters, but this can be solved by having those parameters
as normal ones like `sliced(4, {allowDownsize: true})` and it
creates some maybe unnecessary overhead.
However it is probably the easiest solution right now.
In ggplotd I often use named tuples as and "anonymoous" struct:
Tuple!(double,"x")( 0.0 )
I also added a merge function that will return a tuple containing
merged named tuples:
Tuple!(double,"x",string,"colour")(-1,
"black").merge(Tuple!(double,"x")(0.0))
returns:
Tuple!(double,"x",string,"colour")(0, "black");
As an aside the merge function also works with structs so you can
do the following:
struct Point
{
double x;
double y;
}
Tuple!(double,"x",string,"colour")(-1, "black").merge(Point(1,2))
returns:
Tuple!(double,"x",double,"y",string,"colour")(1, 2, "black");
It works reasonably well, except that the tuples require a lot of
typing.
Re: Memory Efficient HashSet
On Tuesday, 8 March 2016 at 08:12:04 UTC, Nordlöw wrote:
Has anybody put together a memory-efficient D-implementation of
a HashSet
Something like
sparse_hash_set<> contained in
https://github.com/sparsehash/sparsehash
but in D.
There is an implementation in:
code.dlang.org/packages/emsi_containers
But to be honest I got stuck trying to use it (copy constructor
disabled), so I used this very minimal wrapper around associative
array:
private struct HashSet(E) {
// TODO switch to proper implementation (not using AA)
bool put( E el )
{
if ( el in set )
return false;
set[el] = set.length;
return true;
}
size_t[E] set;
}
(I only needed put, since I used it to check whether we already
encountered a value before in a lazy/non sorted implementation of
uniq)
Re: Warning: statement is not reachable
On Tuesday, 1 March 2016 at 21:30:44 UTC, Tamas wrote:
foreach(attr; __traits(getAttributes, S)) {
static if (is(attr == Tag)) {
return true;
}
}
return false;
}();
}
void main() {
static @Tag struct MyStruct {}
static struct VanillaStruct {}
static assert(isTagged!MyStruct);
static assert(!isTagged!VanillaStruct);
}
Sorry forgot to add the fix to the email. The following should
work:
bool tag = false;
foreach(attr; __traits(getAttributes, S)) {
static if (is(attr == Tag)) {
tag = true;
}
}
return tag;
Re: Warning: statement is not reachable
On Tuesday, 1 March 2016 at 21:30:44 UTC, Tamas wrote:
My d code doesn't compile using ldc2 1.0.0-alpha or anything
above DMD v2.068.0
Using these compilers I get a lot of "Warning: statement is not
reachable". Then the both compiler crashes.
ldc2 -w reach.d
dmd -w reach.d
reach.d:
struct Tag {}
template isTagged(S) {
enum bool isTagged =
delegate() {
foreach(attr; __traits(getAttributes, S)) {
static if (is(attr == Tag)) {
return true;
}
}
return false;
}();
}
void main() {
static @Tag struct MyStruct {}
static struct VanillaStruct {}
static assert(isTagged!MyStruct);
static assert(!isTagged!VanillaStruct);
}
We had the same problem in painlessjson and you can find some
more background (with our fix) on it here:
https://github.com/BlackEdder/painlessjson/issues/49
As I understand it: if attr == Tag the code will look something
like this:
foreach(attr; __traits(getAttributes, S)) {
return true;
}
return false;
and the return false is basically unreachable.
Re: Why file.exists of relative path on Linux always return false?
On Monday, 29 February 2016 at 14:58:46 UTC, Alex Parrill wrote:
On Monday, 29 February 2016 at 14:50:51 UTC, Suliman wrote:
I am trying to check relative path on Linux for exists.
string mypath = "~/Documents/imgs";
~ is expanded by your shell. It is not a relative path, and
system calls do not recognize it (same with environmental
variables).
D can expand tilde with expandTilde:
import std.path : expandTilde;
string mypath = expandTilde("~/Documents/imgs");
Re: Am I right understand the dub.json system?
On Monday, 29 February 2016 at 12:45:36 UTC, Suliman wrote:
On Monday, 29 February 2016 at 12:34:02 UTC, Edwin van Leeuwen
wrote:
Should it be like this?
http://www.everfall.com/paste/id.php?80k9jsgdx6o3
"versions": ["VibeCustomMain"],
"versions": ["USE_MYSQL"],
As far as I know all versions should be on one line:
"versions": ["VibeCustomMain","USE_MYSQL"],
And by log it's again try to build sqllite.
What does the log actually say? Is it trying to bind to sqlite?
What happens if you also add
"subConfigurations": {
"ddbc":"MySQL"
}
Re: Am I right understand the dub.json system?
On Monday, 29 February 2016 at 12:27:04 UTC, Suliman wrote: For example I have got app that depended on DDBC. In configuration section DDBC related on: "libs-posix": [ "sqlite3", "pq" ] Does it's mean that it will try to find this 2 libs in any case? Even I do not use them. If I do not need them what I should to do? Fix ~/.dub/packages/ddbc and remove this strings from it, or what? Reading the dub.json from ddbc it seems you can specify which version you want. So if you only need mysql support you add "versions": ["USE_MYSQL"], in your own dub.json file.
Re: Is DUB the best place to get examples of "Best of" D code?
On Sunday, 28 February 2016 at 05:59:39 UTC, WhatMeWorry wrote: If so, is there a way to do a global search of all projects in DUB? If you just want to search through package names and descriptions you can use the search box at the top right of code.dlang.org. If you want to search through code. Most packages are on github, so you could search there (limit by D projects).
