Re: thisExePath purity
On Tuesday, September 20, 2016 04:17:21 crimaniak via Digitalmars-d-learn wrote: > static shared immutable ReturnType!T value; I would point out that immutable is implicitly shared, so there's no reason to put shared on an immutable variable. However, you _do_ want to put shared on a static constructor that initializes an immutable variable so that it's only run once for the program instead of once per thread (the compiler really should enforce that, but there's a longstanding bug that allows you to reinitialize an immutable variable by not putting shared on the static constructor and starting multiple threads). - Jonathan M Davis
Re: thisExePath purity
Hi and thanks all!
On Tuesday, 20 September 2016 at 00:43:10 UTC, Jonathan M Davis
wrote:
immutable string executablePath;
shared static this()
{
import std.file : thisExePath();
executablePath = thisExePath();
}
This code is good for my needs but I start to think about how to
call thisExePath only if it is really used and come to this
solution:
import std.traits: ReturnType, Parameters;
string staticMemoize(alias T, Parms = Parameters!T)() pure
{
struct Holder(alias T)
{
static shared immutable ReturnType!T value;
shared static this(){ value = T(Parms); }
}
return Holder!T.value;
}
unittest
{
import std.file : thisExePath;
assert(staticMemoize!thisExePath == thisExePath);
}
Something like this. Need to refine about input parameters, but I
hope, idea is clear.
Unlike the function memoize from phobos staticMemoize really
pure. And unlike proposed solution with ordinary variable
staticMemoize is lazy, because no call - no instantiation.
https://dlang.org/library/std/functional/memoize.html
Re: polar coordinates with ggplotd
On Monday, 19 September 2016 at 12:34:56 UTC, Edwin van Leeuwen wrote: 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. Yeah, problem solved. Thanks.
Re: thisExePath purity
On Tuesday, September 20, 2016 00:37:10 Stefan Koch via Digitalmars-d-learn wrote: > On Tuesday, 20 September 2016 at 00:01:58 UTC, crimaniak wrote: > > Hi! > > > > Is there situations when output of thisExePath() can be > > different during runtime? If yes, what the reason? > > If no, is this possible to mark it as pure in phobos? > > > > https://dlang.org/library/std/file/this_exe_path.html > > No way to do that. > It does I/O. > However you cheat. > look for assumePure in https://dlang.org/phobos/std_traits.html > and then you can create a wrapper for it that is fake pure. Yes, you can cast a function pointer to force purity, but that's almost always a bad idea. It makes far more sense to just grab the value once and reuse it. The only time that I'd suggest using the casting trick for something like this would be when you can't afford to use static constructors, and you can't afford to pass the value around. Casting to pure should be a tool of last resort. It _is_ an option though if you really have no reasonable alternative. Another thing to consider in this case is that casting like that would actually be needlessly expensive if he actually needs to make the call more than once. It would be far cheaper to just save the result and reuse it. And if it's stored in an immutable module-level or static variable, then it can be used in a pure function. - Jonathan M Davis
Re: thisExePath purity
On Tuesday, September 20, 2016 00:01:58 crimaniak via Digitalmars-d-learn
wrote:
> Hi!
>
> Is there situations when output of thisExePath() can be different
> during runtime? If yes, what the reason?
> If no, is this possible to mark it as pure in phobos?
>
> https://dlang.org/library/std/file/this_exe_path.html
In principle, it should be impossible for it to change while the program is
running. However, what Phobos has to do to get the information can't be
pure. In the best case, it involves calling C functions that we can
reasonably assume will be pure but can't technically guarantee will be, but
in some cases, it actually involves querying the file system (e.g. on Linux,
it reads "/proc/self/exe"), which definitely can't be pure, because it
involves I/O.
If you really want a pure way to deal with this, then I'd suggest grabbing
the value at startup and setting it to an immutable variable. e.g. something
like
immutable string executablePath;
shared static this()
{
import std.file : thisExePath();
executablePath = thisExePath();
}
and then you can use that variable in pure code, because it's guaranteed not
to change.
- Jonathan M Davis
Re: thisExePath purity
On 9/19/16 8:01 PM, crimaniak wrote:
Hi!
Is there situations when output of thisExePath() can be different during
runtime? If yes, what the reason?
If no, is this possible to mark it as pure in phobos?
https://dlang.org/library/std/file/this_exe_path.html
Not in a way that D can ensure purity. Yes, it will not change. But that
guarantee is not communicated via the OS functions required to call to
get the information.
One thing you can do:
immutable string myPath;
shared static this()
{
import std.file: thisExePath;
myPath = thisExePath;
}
// now use myPath as required from pure functions.
-Steve
Re: thisExePath purity
On Tuesday, 20 September 2016 at 00:01:58 UTC, crimaniak wrote: Hi! Is there situations when output of thisExePath() can be different during runtime? If yes, what the reason? If no, is this possible to mark it as pure in phobos? https://dlang.org/library/std/file/this_exe_path.html No way to do that. It does I/O. However you cheat. look for assumePure in https://dlang.org/phobos/std_traits.html and then you can create a wrapper for it that is fake pure.
thisExePath purity
Hi! Is there situations when output of thisExePath() can be different during runtime? If yes, what the reason? If no, is this possible to mark it as pure in phobos? https://dlang.org/library/std/file/this_exe_path.html
Re: What blogs about D do you read?
On Monday, 19 September 2016 at 21:49:04 UTC, Ali Çehreli wrote: https://atilanevesoncode.wordpress.com/ Ali Thanks, Ali.
Re: What blogs about D do you read?
On 09/19/2016 01:20 PM, Guillaume Piolat wrote: On Monday, 19 September 2016 at 17:42:51 UTC, A D dev wrote: Hi list, What blogs about D do you read? Thanks in advance. https://dlang.org/blog/ http://dblog.aldacron.net/ http://minas-mina.com/ http://nomad.so/tag/d/ http://blog.thecybershadow.net/ https://p0nce.github.io/d-idioms/ (disclaimer: my own) https://atilanevesoncode.wordpress.com/ Ali
Re: What exactly does the compiler switch -betterC do?
On Monday, 20 June 2016 at 06:35:32 UTC, Jacob Carlborg wrote:
On 2016-06-19 21:53, Gary Willoughby wrote:
When compiling, what exactly does the -betterC flag do? The
command help
says "omit generating some runtime information and helper
functions" but
what does this really mean? Is there any specifics somewhere?
It is intended to allow you to link an application without
druntime. A Hello World using "extern(C) main" and printing
using "printf" contains the following symbols on OS X:
00a8 S _D4main12__ModuleInfoZ
0068 T _D4main15__unittest_failFiZv
0018 T _D4main7__arrayZ
0040 T _D4main8__assertFiZv
00b5 s _TMP1
U __d_arraybounds
U __d_assert
U __d_unittest
T _main
U _printf
If compiled with -betterC, it contains these:
T _main
U _printf
I get significantly more symbols than that when compiling the
following program any idea why?
import core.stdc.stdio;
extern(C) void main()
{
printf("Hello World!\n");
}
$ rdmd --build-only --force -betterC -de -O -inline -release -w
test.d
$ nm test
Re: What blogs about D do you read?
On Monday, 19 September 2016 at 20:20:26 UTC, Guillaume Piolat wrote: https://dlang.org/blog/ http://dblog.aldacron.net/ http://minas-mina.com/ http://nomad.so/tag/d/ http://blog.thecybershadow.net/ https://p0nce.github.io/d-idioms/ (disclaimer: my own) Great, thanks!
Re: What blogs about D do you read?
On Monday, 19 September 2016 at 17:42:51 UTC, A D dev wrote: Hi list, What blogs about D do you read? Thanks in advance. https://dlang.org/blog/ http://dblog.aldacron.net/ http://minas-mina.com/ http://nomad.so/tag/d/ http://blog.thecybershadow.net/ https://p0nce.github.io/d-idioms/ (disclaimer: my own)
Re: What blogs about D do you read?
On Monday, 19 September 2016 at 19:36:22 UTC, Karabuta wrote: I have one here on Vibe.d for beginners https://laberba.github.io/2016/hello-world-app-with-the-vibe.d-web-framework/ I will be writing more for-beginners blogs in the coming few weeks. Thank you. Will read it.
Re: What blogs about D do you read?
On Monday, 19 September 2016 at 19:29:25 UTC, A D dev wrote: On Monday, 19 September 2016 at 17:42:51 UTC, A D dev wrote: Hi list, What blogs about D do you read? To be more clear: - what blogs that include posts on D, would you recommend to a D beginner? Thanks. I have one here on Vibe.d for beginners https://laberba.github.io/2016/hello-world-app-with-the-vibe.d-web-framework/ I will be writing more for-beginners blogs in the coming few weeks.
Re: What blogs about D do you read?
On Monday, 19 September 2016 at 17:42:51 UTC, A D dev wrote: Hi list, What blogs about D do you read? To be more clear: - what blogs that include posts on D, would you recommend to a D beginner? Thanks.
Re: Iterate over two arguments at once
On Monday, 19 September 2016 at 18:10:22 UTC, bachmeier wrote:
Suppose I want to iterate over two arrays at once:
foreach(v1, v2; [1.5, 2.5, 3.5], [4.5, 5.5, 6.5]) {
...
}
I have seen a way to do this but cannot remember what it is and
cannot find it.
Thanks for the replies. This is what I needed.
Re: Iterate over two arguments at once
On Monday, 19 September 2016 at 18:10:22 UTC, bachmeier wrote:
Suppose I want to iterate over two arrays at once:
foreach(v1, v2; [1.5, 2.5, 3.5], [4.5, 5.5, 6.5]) {
...
}
I have seen a way to do this but cannot remember what it is and
cannot find it.
range.lockstep: https://dlang.org/phobos/std_range.html#lockstep
Re: Iterate over two arguments at once
On 9/19/16 2:10 PM, bachmeier wrote:
Suppose I want to iterate over two arrays at once:
foreach(v1, v2; [1.5, 2.5, 3.5], [4.5, 5.5, 6.5]) {
...
}
I have seen a way to do this but cannot remember what it is and cannot
find it.
http://dlang.org/phobos/std_range.html#.zip
-Steve
Re: Iterate over two arguments at once
On Monday, 19 September 2016 at 18:10:22 UTC, bachmeier wrote:
Suppose I want to iterate over two arrays at once:
foreach(v1, v2; [1.5, 2.5, 3.5], [4.5, 5.5, 6.5]) {
...
}
I have seen a way to do this but cannot remember what it is and
cannot find it.
You can use std.range.zip:
https://dlang.org/phobos/std_range.html#.zip
Or std.range.lockstep:
https://dlang.org/phobos/std_range.html#.lockstep
Re: vibe.d maxRequestSize
On Monday, 19 September 2016 at 17:54:05 UTC, Steven Schveighoffer wrote: On 9/19/16 1:34 PM, Chris wrote: [...] Here is the culprit: https://github.com/rejectedsoftware/vibe.d/blob/0.7.29/source/vibe/http/server.d#L1861 And the definition of MaxHTTPHeaderLineLength is: https://github.com/rejectedsoftware/vibe.d/blob/0.7.29/source/vibe/http/server.d#L1861 4096 bytes. I'm not super-familiar with HTTP protocol requirements, but a further diagnosis of your net traffic may reveal that your browser is doing something unorthodox, or vibe needs to adjust here. -Steve Thanks a million! I'll look into it tomorrow.
Iterate over two arguments at once
Suppose I want to iterate over two arrays at once:
foreach(v1, v2; [1.5, 2.5, 3.5], [4.5, 5.5, 6.5]) {
...
}
I have seen a way to do this but cannot remember what it is and
cannot find it.
Re: vibe.d maxRequestSize
On 9/19/16 1:34 PM, Chris wrote: On Monday, 19 September 2016 at 16:55:05 UTC, Steven Schveighoffer wrote: Hm... you don't get a full stack trace? Hard to tell what max_bytes should be, it defaults to ulong.max, so no way you are exhausting that. Without knowing where readUntilSmall is called, it's hard to diagnose. -Steve I didn't want to litter the thread, here it is: 400 - Bad Request Bad Request Internal error information: object.Exception@../../.dub/packages/vibe-d-0.7.29/vibe-d/source/vibe/stream/operations.d(349): Reached maximum number of bytes while searching for end marker. /home/chris/.dvm/compilers/dmd-2.071.1/linux/bin/../../src/phobos/std/exception.d:405 pure @safe void std.exception.bailOut!(Exception).bailOut(immutable(char)[], ulong, const(char[])) [0x8f11a7] /home/chris/.dvm/compilers/dmd-2.071.1/linux/bin/../../src/phobos/std/exception.d:363 pure @safe bool std.exception.enforce!(Exception, bool).enforce(bool, lazy const(char)[], immutable(char)[], ulong) [0x8f112a] .../../.dub/packages/vibe-d-0.7.29/vibe-d/source/vibe/stream/operations.d:348 void vibe.stream.operations.readUntilSmall!(vibe.utils.array.AllocAppender!(ubyte[], ubyte).AllocAppender).readUntilSmall(vibe.core.stream.InputStream, ref vibe.utils.array.AllocAppender!(ubyte[], ubyte).AllocAppender, const(ubyte[]), ulong) [0xb06b00] .../../.dub/packages/vibe-d-0.7.29/vibe-d/source/vibe/stream/operations.d:137 void vibe.stream.operations.readUntil!(vibe.utils.array.AllocAppender!(ubyte[], ubyte).AllocAppender).readUntil(vibe.core.stream.InputStream, ref vibe.utils.array.AllocAppender!(ubyte[], ubyte).AllocAppender, const(ubyte[]), ulong) [0xb06a1f] .../../.dub/packages/vibe-d-0.7.29/vibe-d/source/vibe/stream/operations.d:53 void vibe.stream.operations.readLine!(vibe.utils.array.AllocAppender!(ubyte[], ubyte).AllocAppender).readLine(vibe.core.stream.InputStream, ref vibe.utils.array.AllocAppender!(ubyte[], ubyte).AllocAppender, ulong, immutable(char)[]) [0xb069c8] .../../.dub/packages/vibe-d-0.7.29/vibe-d/source/vibe/stream/operations.d:39 ubyte[] vibe.stream.operations.readLine!().readLine(vibe.core.stream.InputStream, ulong, immutable(char)[], vibe.utils.memory.Allocator) [0xb06984] .../../.dub/packages/vibe-d-0.7.29/vibe-d/source/vibe/http/server.d:1861 void vibe.http.server.parseRequestHeader(vibe.http.server.HTTPServerRequest, vibe.core.stream.InputStream, vibe.utils.memory.Allocator, ulong) [0xb5e827] Here is the culprit: https://github.com/rejectedsoftware/vibe.d/blob/0.7.29/source/vibe/http/server.d#L1861 And the definition of MaxHTTPHeaderLineLength is: https://github.com/rejectedsoftware/vibe.d/blob/0.7.29/source/vibe/http/server.d#L1861 4096 bytes. I'm not super-familiar with HTTP protocol requirements, but a further diagnosis of your net traffic may reveal that your browser is doing something unorthodox, or vibe needs to adjust here. -Steve
What blogs about D do you read?
Hi list, What blogs about D do you read? Thanks in advance.
Re: vibe.d maxRequestSize
On Monday, 19 September 2016 at 16:55:05 UTC, Steven Schveighoffer wrote: Hm... you don't get a full stack trace? Hard to tell what max_bytes should be, it defaults to ulong.max, so no way you are exhausting that. Without knowing where readUntilSmall is called, it's hard to diagnose. -Steve I didn't want to litter the thread, here it is: 400 - Bad Request Bad Request Internal error information: object.Exception@../../.dub/packages/vibe-d-0.7.29/vibe-d/source/vibe/stream/operations.d(349): Reached maximum number of bytes while searching for end marker. /home/chris/.dvm/compilers/dmd-2.071.1/linux/bin/../../src/phobos/std/exception.d:405 pure @safe void std.exception.bailOut!(Exception).bailOut(immutable(char)[], ulong, const(char[])) [0x8f11a7] /home/chris/.dvm/compilers/dmd-2.071.1/linux/bin/../../src/phobos/std/exception.d:363 pure @safe bool std.exception.enforce!(Exception, bool).enforce(bool, lazy const(char)[], immutable(char)[], ulong) [0x8f112a] ../../.dub/packages/vibe-d-0.7.29/vibe-d/source/vibe/stream/operations.d:348 void vibe.stream.operations.readUntilSmall!(vibe.utils.array.AllocAppender!(ubyte[], ubyte).AllocAppender).readUntilSmall(vibe.core.stream.InputStream, ref vibe.utils.array.AllocAppender!(ubyte[], ubyte).AllocAppender, const(ubyte[]), ulong) [0xb06b00] ../../.dub/packages/vibe-d-0.7.29/vibe-d/source/vibe/stream/operations.d:137 void vibe.stream.operations.readUntil!(vibe.utils.array.AllocAppender!(ubyte[], ubyte).AllocAppender).readUntil(vibe.core.stream.InputStream, ref vibe.utils.array.AllocAppender!(ubyte[], ubyte).AllocAppender, const(ubyte[]), ulong) [0xb06a1f] ../../.dub/packages/vibe-d-0.7.29/vibe-d/source/vibe/stream/operations.d:53 void vibe.stream.operations.readLine!(vibe.utils.array.AllocAppender!(ubyte[], ubyte).AllocAppender).readLine(vibe.core.stream.InputStream, ref vibe.utils.array.AllocAppender!(ubyte[], ubyte).AllocAppender, ulong, immutable(char)[]) [0xb069c8] ../../.dub/packages/vibe-d-0.7.29/vibe-d/source/vibe/stream/operations.d:39 ubyte[] vibe.stream.operations.readLine!().readLine(vibe.core.stream.InputStream, ulong, immutable(char)[], vibe.utils.memory.Allocator) [0xb06984] ../../.dub/packages/vibe-d-0.7.29/vibe-d/source/vibe/http/server.d:1861 void vibe.http.server.parseRequestHeader(vibe.http.server.HTTPServerRequest, vibe.core.stream.InputStream, vibe.utils.memory.Allocator, ulong) [0xb5e827] ../../.dub/packages/vibe-d-0.7.29/vibe-d/source/vibe/http/server.d:1659 bool vibe.http.server.handleRequest(vibe.core.stream.Stream, vibe.core.net.TCPConnection, vibe.http.server.HTTPListenInfo, ref vibe.http.server.HTTPServerSettings, ref bool) [0xb5c5d0] ../../.dub/packages/vibe-d-0.7.29/vibe-d/source/vibe/http/server.d:1552 void vibe.http.server.handleHTTPConnection(vibe.core.net.TCPConnection, vibe.http.server.HTTPListenInfo) [0xb5be4e] ../../.dub/packages/vibe-d-0.7.29/vibe-d/source/vibe/http/server.d:1433 void vibe.http.server.listenHTTPPlain(vibe.http.server.HTTPServerSettings).doListen(vibe.http.server.HTTPListenInfo, bool, bool).__lambda4(vibe.core.net.TCPConnection) [0xb5b814] ../../.dub/packages/vibe-d-0.7.29/vibe-d/source/vibe/core/drivers/libevent2_tcp.d:610 void vibe.core.drivers.libevent2_tcp.ClientTask.execute() [0xbe8715] ../../.dub/packages/vibe-d-0.7.29/vibe-d/source/vibe/core/core.d:488 void vibe.core.core.makeTaskFuncInfo!(void delegate()).makeTaskFuncInfo(ref void delegate()).callDelegate(vibe.core.core.TaskFuncInfo*) [0xafea75] ../../.dub/packages/vibe-d-0.7.29/vibe-d/source/vibe/core/core.d:1119 void vibe.core.core.CoreTask.run() [0xb8dd79] ??:? void core.thread.Fiber.run() [0xc70ea5] ??:? fiber_entryPoint [0xc70c27] ??:? [0x]
Re: vibe.d maxRequestSize
On 9/19/16 11:59 AM, Chris wrote: On Thursday, 15 September 2016 at 13:26:48 UTC, Steven Schveighoffer wrote: On 9/15/16 9:11 AM, Chris wrote: On Wednesday, 14 September 2016 at 20:23:09 UTC, Steven Schveighoffer wrote: Hm.. I have adjusted this in my project, and it works (set to 50M). Needed it for uploading large images. Using version 0.7.29 It doesn't seem to make any difference in my case. I wonder what could be wrong Seems to be in use: https://github.com/rejectedsoftware/vibe.d/blob/master/source/vibe/http/server.d#L1832 Finally, I could find where it happens. If I use "get" in a HTML form (instead of "post"), vibe.d complains. I set the max request and request header size to 25MB. ` 400 - Bad Request Bad Request Internal error information: object.Exception@../../.dub/packages/vibe-d-0.7.29/vibe-d/source/vibe/stream/operations.d(349): Reached maximum number of bytes while searching for end marker. ` https://github.com/rejectedsoftware/vibe.d/blob/master/source/vibe/stream/operations.d#L349 Hm... you don't get a full stack trace? Hard to tell what max_bytes should be, it defaults to ulong.max, so no way you are exhausting that. Without knowing where readUntilSmall is called, it's hard to diagnose. -Steve
Re: seg fault, now what?
On Saturday, 17 September 2016 at 21:12:08 UTC, Ryan wrote: But I don't have another e-mail address, and it seems a bit much to create a fake e-mail account for a few bug reports. mailmetrash.com :)
Re: vibe.d maxRequestSize
On Thursday, 15 September 2016 at 13:26:48 UTC, Steven Schveighoffer wrote: On 9/15/16 9:11 AM, Chris wrote: On Wednesday, 14 September 2016 at 20:23:09 UTC, Steven Schveighoffer wrote: Hm.. I have adjusted this in my project, and it works (set to 50M). Needed it for uploading large images. Using version 0.7.29 -Steve It doesn't seem to make any difference in my case. I wonder what could be wrong Seems to be in use: https://github.com/rejectedsoftware/vibe.d/blob/master/source/vibe/http/server.d#L1832 -Steve Finally, I could find where it happens. If I use "get" in a HTML form (instead of "post"), vibe.d complains. I set the max request and request header size to 25MB. ` 400 - Bad Request Bad Request Internal error information: object.Exception@../../.dub/packages/vibe-d-0.7.29/vibe-d/source/vibe/stream/operations.d(349): Reached maximum number of bytes while searching for end marker. ` https://github.com/rejectedsoftware/vibe.d/blob/master/source/vibe/stream/operations.d#L349
Re: seg fault, now what?
On 9/17/16 5:12 PM, Ryan wrote: Is there an alternative to reporting bugs via bugzilla? I tried to open an account, but they recommend not using your main e-mail address because it will be posted to the web for all the spammers to find. But I don't have another e-mail address, and it seems a bit much to create a fake e-mail account for a few bug reports. Slightly OT, but with a gmail/yahoo address, generally the spam filter is quite good. I've used my yahoo address for years on bugzilla and this forum, and never had adverse spamming issues. -Steve
Re: Forum for new programmers in spanish.
On Monday, 19 September 2016 at 10:10:18 UTC, Seb wrote: I don't speak Spanish, but I do like your idea of bringing D to more people :) Two ideas: 1) You could help to translate the DLang Tour to Spanish: https://tour.dlang.org https://github.com/dlang-tour/spanish 2) StackOverflow has an excellent PageRank and thus many communities are moving there discussions over as it helps to increase their visibility and searchability. I don't know how good the spanish StackOverflow is, but it might be easier than maintaining a forum yourself? Thanks Seb. I'll look at the DLang Tour. On the other hand, i think a forum will be better, not only to help, but also to keep D programmers closer and expectant for news. Although, you are right, StackOverflow would be better to increase searchability and easier than maintaining a forum. I'll keep that in mind before taking a decision. Thanks!
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: Forum for new programmers in spanish.
On Monday, 19 September 2016 at 05:56:04 UTC, Geert wrote: Hi all! I'm a PHP programmer, and i've been searching for new languages to learn. I think D it's the best of the newest languages, due its good documentation, clean sintaxis (or less verbose), and the applications developed in D run fast. I've read a D application could run as fast as one devoloped in C++ if it's well optimized (this is what interests me most). I think D has a good community wich is constantly growing. But i have not found good resources of it in my native language: spanish. It is for this reason that i was thinking on developing a D spanish forum in my own server, to help new programmers who don't speak english. I think a divided community takes longer to reach a target, and that is not my intention. I would like anyone who speaks english stays and make contributions here. What do you think about it? I don't speak Spanish, but I do like your idea of bringing D to more people :) Two ideas: 1) You could help to translate the DLang Tour to Spanish: https://tour.dlang.org https://github.com/dlang-tour/spanish 2) StackOverflow has an excellent PageRank and thus many communities are moving there discussions over as it helps to increase their visibility and searchability. I don't know how good the spanish StackOverflow is, but it might be easier than maintaining a forum yourself?
Help with "cannot alias an expression" compile error
I'm trying to do some form of reflection abstraction, here's my sample code:
import std.meta;
struct Fields(T)
{
private static alias toField(alias e) = Field!(__traits(identifier,
e));
alias fields = staticMap!(toField, T.tupleof);
static alias map(alias F) = staticMap!(F, fields);
static alias filter(alias pred) = Filter!(pred, fields);
}
struct Field(string n)
{
enum name = n;
}
struct Foo
{
int a;
}
void main()
{
Foo value;
enum toName(alias e) = e.name;
enum pred(alias e) = true;
alias a = Fields!(Foo).filter!(pred); // works
alias b = Fields!(Foo).map!(toName); // works
alias c = Fields!(Foo).init.filter!(pred); // works
alias d = Fields!(Foo).init.map!(toName); // Error: alias d cannot
alias an expression Fields().tuple("a")
}
Alias "a" and "b" compiles just fine. Alias "c" compiles as well but not
alias "d", which I don't understand why. I'm fully aware that it's not
possible to alias an expression, but what I want is to alias the tuple
of strings that is returned.
--
/Jacob Carlborg
Forum for new programmers in spanish.
Hi all! I'm a PHP programmer, and i've been searching for new languages to learn. I think D it's the best of the newest languages, due its good documentation, clean sintaxis (or less verbose), and the applications developed in D run fast. I've read a D application could run as fast as one devoloped in C++ if it's well optimized (this is what interests me most). I think D has a good community wich is constantly growing. But i have not found good resources of it in my native language: spanish. It is for this reason that i was thinking on developing a D spanish forum in my own server, to help new programmers who don't speak english. I think a divided community takes longer to reach a target, and that is not my intention. I would like anyone who speaks english stays and make contributions here. What do you think about it?
