Re: UFCS with implicit "this" ?
On Tuesday, August 09, 2016 05:13:44 cy via Digitalmars-d-learn wrote:
> I really like UFCS, which is to say, defining functions outside
> the class/struct to operate on it, but you can still say
> object.function(...) and it'll get rewritten into
> function(object,...).
>
> Only sticky point is the convenience of "this". Like I can go
>
> struct A {
> bool a;
> bool b;
> bool c;
> bool d;
> bool foo() {
> return a && b || c && !d;
> }
> }
>
> But if I try do do the same thing with "bool bar(A object)" I end
> up with this:
>
> bool bar(A object) {
> return object.a && object.b || object.c && !object.d;
> }
>
> My example is a bit contrived, but it occurred to me how neat it
> would be if we could just specify "implicit" objects in our
> current scope.
Personally, I think that you should just make it a member function if it's
not a generic function, but to each their own, I suppose. Regardless,
there's already a feature to do what you're looking for - with statements.
e.g.
bool bar(A object)
{
with(object)
return a && b || c && !d;
}
https://dlang.org/spec/statement.html#WithStatement
- Jonathan M Davis
UFCS with implicit "this" ?
I really like UFCS, which is to say, defining functions outside
the class/struct to operate on it, but you can still say
object.function(...) and it'll get rewritten into
function(object,...).
Only sticky point is the convenience of "this". Like I can go
struct A {
bool a;
bool b;
bool c;
bool d;
bool foo() {
return a && b || c && !d;
}
}
But if I try do do the same thing with "bool bar(A object)" I end
up with this:
bool bar(A object) {
return object.a && object.b || object.c && !object.d;
}
My example is a bit contrived, but it occurred to me how neat it
would be if we could just specify "implicit" objects in our
current scope. Like I was messing with an RGB and an HSL object,
and I ended up having things like:
hsl.saturation = (max(rgb.r,rgb.g,rgb.b) -
min(rgb.r,rgb.g,rgb.b)) / (2 - max(rgb.r,rgb.g,rgb.b) -
min(rgb.r,rgb.g.rgb.b))
when I wanted something more like this:
saturation = (max(r,g,b) - min(r,g,b)) / (2 - max(r,g,b) -
min(r,g,b)
Is there any way to do that in D? They don't let you use "alias
this rgb" for a function scope, only a type's scope, so I guess
it isn't possible?
I mean, aside from making an inner structure to the function, and
copying the object by value... that's even more confusing than
worth the convenience.
Re: Pass RegexMatch to a function?
On Tuesday, August 09, 2016 01:07:53 Gerald via Digitalmars-d-learn wrote:
> I have a RegexMatch that I want to pass to a function that takes
> the match and replaces various tokens in a string with the match
> and/or individual groups of the match. I'm struggling to figure
> out how to pass a RegexMatch to a function, right now I have code
> like the follows:
>
> RegexMatch regexMatch = matchAll(urlMatch.match,
> regex(tr.pattern, tr.caseless?"i":""));
> string command = replaceMatchTokens(urlMatch.match, regexMatch);
>
> ...
>
> string replaceMatchTokens(string tokenizedText, ref RegexMatch
> match) {
> string result = tokenizedText.replace("$0", match.match);
>
> int i = 0;
> foreach(group; match.captures) {
> result = result.replace("$" ~ to!string(i), group);
> i++;
> }
> return result;
> }
>
> When I try to compile this, it fails with the follow on the line
> where replaceMatchTokens is declared:
>
> Error: struct std.regex.RegexMatch(R, alias Engine =
> ThompsonMatcher) if (isSomeString!R) is used as a type
>
> I've also tried declaring it as follows:
>
> string replaceMatchTokens(string tokenizedText, ref
> RegexMatch!(string, ThompsonMatcher) match) {
>
> With the following errors:
>
> source/gx/terminix/terminal/terminal.d(1273,28): Error: struct
> std.regex.RegexMatch(R, alias Engine = ThompsonMatcher) if
> (isSomeString!R) is used as a type
> source/gx/terminix/terminal/terminal.d(2701,54): Error: template
> std.regex.match cannot deduce function from argument types
> !()(RegexMatch!(string, ThompsonMatcher)), candidates are:
> /usr/include/dlang/dmd/std/regex/package.d(777,13):
> std.regex.match(R, RegEx)(R input, RegEx re) if (isSomeString!R
> && is(RegEx == Regex!(BasicElementOf!R)))
> /usr/include/dlang/dmd/std/regex/package.d(785,13):
> std.regex.match(R, String)(R input, String re) if (isSomeString!R
> && isSomeString!String)
> /usr/include/dlang/dmd/std/regex/package.d(792,13):
> std.regex.match(R, RegEx)(R input, RegEx re) if (isSomeString!R
> && is(RegEx == StaticRegex!(BasicElementOf!R)))
RegexMatch is a templated type, so if you type RegexMatch, you're not
providing an actual type - just the name of the template used to generate a
type. For instance, if you have
struct S(T)
{
T member;
}
S would be meaningless in most cases. It would be instantiations of S such
as S!int or S!string which would actually be types. Almost always, the
solution when dealing with templated types is to templatize your function
(you can specify the exact instantiation you're using, but that can get
pretty ugly. In this case, what you probably want is something like
string replaceMatchTokens(RM)(string tokenizedText, RM match)
if(std.traits.isInstanceOf(RegexMatch, RM))
{
...
}
- Jonathan M Davis
Pass RegexMatch to a function?
I have a RegexMatch that I want to pass to a function that takes
the match and replaces various tokens in a string with the match
and/or individual groups of the match. I'm struggling to figure
out how to pass a RegexMatch to a function, right now I have code
like the follows:
RegexMatch regexMatch = matchAll(urlMatch.match,
regex(tr.pattern, tr.caseless?"i":""));
string command = replaceMatchTokens(urlMatch.match, regexMatch);
...
string replaceMatchTokens(string tokenizedText, ref RegexMatch
match) {
string result = tokenizedText.replace("$0", match.match);
int i = 0;
foreach(group; match.captures) {
result = result.replace("$" ~ to!string(i), group);
i++;
}
return result;
}
When I try to compile this, it fails with the follow on the line
where replaceMatchTokens is declared:
Error: struct std.regex.RegexMatch(R, alias Engine =
ThompsonMatcher) if (isSomeString!R) is used as a type
I've also tried declaring it as follows:
string replaceMatchTokens(string tokenizedText, ref
RegexMatch!(string, ThompsonMatcher) match) {
With the following errors:
source/gx/terminix/terminal/terminal.d(1273,28): Error: struct
std.regex.RegexMatch(R, alias Engine = ThompsonMatcher) if
(isSomeString!R) is used as a type
source/gx/terminix/terminal/terminal.d(2701,54): Error: template
std.regex.match cannot deduce function from argument types
!()(RegexMatch!(string, ThompsonMatcher)), candidates are:
/usr/include/dlang/dmd/std/regex/package.d(777,13):
std.regex.match(R, RegEx)(R input, RegEx re) if (isSomeString!R
&& is(RegEx == Regex!(BasicElementOf!R)))
/usr/include/dlang/dmd/std/regex/package.d(785,13):
std.regex.match(R, String)(R input, String re) if (isSomeString!R
&& isSomeString!String)
/usr/include/dlang/dmd/std/regex/package.d(792,13):
std.regex.match(R, RegEx)(R input, RegEx re) if (isSomeString!R
&& is(RegEx == StaticRegex!(BasicElementOf!R)))
Re: encoding ISO-8859-1 to UTF-8 in std.net.curl
On 08/09/2016 12:05 AM, Alexsej wrote: //header from server server: nginx date: Mon, 08 Aug 2016 22:02:15 GMT content-type: text/xml; Charset=utf-8 content-length: 204 connection: keep-alive vary: Accept-Encoding cache-control: private expires: Mon, 08 Aug 2016 22:02:15 GMT set-cookie: ASPSESSIONIDSSCCDASA=KIAPMCMDMPEDHPBJNMGFHMEB; path=/ x-powered-by: ASP.NET Looks like std.net.curl doesn't handle "Charset" correctly. It only works with lowercase "charset". https://github.com/dlang/phobos/pull/4723
Re: encoding ISO-8859-1 to UTF-8 in std.net.curl
On Monday, 8 August 2016 at 21:11:26 UTC, ag0aep6g wrote:
On 08/08/2016 09:57 PM, Alexsej wrote:
// content in ISO-8859-1 to UTF-8 encoding but I lose
//the Cyrillic "отсутствует или неверно задан параметр"
// I get it "оÑÑÑÑÑÑвÑÐµÑ Ð¸Ð»Ð¸ невеÑно
задан паÑамеÑÑ"
// How do I change the encoding to UTF-8 in response
string s = cast(immutable char[])content;
auto f = File("output.txt","w"); // output.txt file in
UTF-8;
f.write(s);
The server doesn't include the encoding in the Content-Type
header, right? So curl assumes the default, which is ISO
8859-1. It interprets the data as that and transcodes to UTF-8.
The result is garbage, of course.
I don't see a way to change the default encoding. Maybe that
should be added.
Until then you can reverse the wrong transcoding:
import std.encoding: Latin1String, transcode;
Latin1String pseudo_latin1;
transcode(content.idup, pseudo_latin1);
string s = cast(string) pseudo_latin1;
Tiny rant:
Why on earth does transcode only accept immutable characters
for input? Every other post here uncovers some bug/shortcoming
:(
thanks it works.
Re: encoding ISO-8859-1 to UTF-8 in std.net.curl
On 08/08/2016 11:11 PM, ag0aep6g wrote: Why on earth does transcode only accept immutable characters for input? https://github.com/dlang/phobos/pull/4722
Re: encoding ISO-8859-1 to UTF-8 in std.net.curl
On Monday, 8 August 2016 at 21:11:26 UTC, ag0aep6g wrote:
On 08/08/2016 09:57 PM, Alexsej wrote:
// content in ISO-8859-1 to UTF-8 encoding but I lose
//the Cyrillic "отсутствует или неверно задан параметр"
// I get it "оÑÑÑÑÑÑвÑÐµÑ Ð¸Ð»Ð¸ невеÑно
задан паÑамеÑÑ"
// How do I change the encoding to UTF-8 in response
string s = cast(immutable char[])content;
auto f = File("output.txt","w"); // output.txt file in
UTF-8;
f.write(s);
The server doesn't include the encoding in the Content-Type
header, right? So curl assumes the default, which is ISO
8859-1. It interprets the data as that and transcodes to UTF-8.
The result is garbage, of course.
I don't see a way to change the default encoding. Maybe that
should be added.
Until then you can reverse the wrong transcoding:
import std.encoding: Latin1String, transcode;
Latin1String pseudo_latin1;
transcode(content.idup, pseudo_latin1);
string s = cast(string) pseudo_latin1;
Tiny rant:
Why on earth does transcode only accept immutable characters
for input? Every other post here uncovers some bug/shortcoming
:(
//header from server
server: nginx
date: Mon, 08 Aug 2016 22:02:15 GMT
content-type: text/xml; Charset=utf-8
content-length: 204
connection: keep-alive
vary: Accept-Encoding
cache-control: private
expires: Mon, 08 Aug 2016 22:02:15 GMT
set-cookie: ASPSESSIONIDSSCCDASA=KIAPMCMDMPEDHPBJNMGFHMEB; path=/
x-powered-by: ASP.NET
arrays, mmu, addressing choices
I have a rather large array that I intend to build. but much of it will only occasionally be used. Will the unused sections automatically be paged out? If it matters my system is Debian Linux. This array will be indexed by a ulong. Is there any reasonable maximum size? I've considered segmented addressing anyway, in case that's needed to allow paging, and it will definitely be needed when I get around to concurrent processing, with different sections resident in different threads. But if appropriate I could do that from the start. The questions above are really for a normal array, but I'd also be interested in how using an associative array would affect them. I expect to eventually be using more memory than I have RAM in my system, so designing for paging is going to be important. (Before then I'll be adding more RAM and a larger disk drive, but if I complete the full design even a large disk is going to be small.)
Re: encoding ISO-8859-1 to UTF-8 in std.net.curl
On 08/08/2016 09:57 PM, Alexsej wrote:
// content in ISO-8859-1 to UTF-8 encoding but I lose
//the Cyrillic "отсутствует или неверно задан параметр"
// I get it "оÑÑÑÑÑÑвÑÐµÑ Ð¸Ð»Ð¸ невеÑно
задан паÑамеÑÑ"
// How do I change the encoding to UTF-8 in response
string s = cast(immutable char[])content;
auto f = File("output.txt","w"); // output.txt file in UTF-8;
f.write(s);
The server doesn't include the encoding in the Content-Type header,
right? So curl assumes the default, which is ISO 8859-1. It interprets
the data as that and transcodes to UTF-8. The result is garbage, of course.
I don't see a way to change the default encoding. Maybe that should be
added.
Until then you can reverse the wrong transcoding:
import std.encoding: Latin1String, transcode;
Latin1String pseudo_latin1;
transcode(content.idup, pseudo_latin1);
string s = cast(string) pseudo_latin1;
Tiny rant:
Why on earth does transcode only accept immutable characters for input?
Every other post here uncovers some bug/shortcoming :(
Re: How do i convert this Makefile to dub
On 08.08.2016 21:48, Adil wrote: On Monday, 8 August 2016 at 18:45:35 UTC, drug007 wrote: On 08.08.2016 21:35, Adil wrote: On Monday, 8 August 2016 at 18:29:54 UTC, Adil wrote: [...] One minor addition. I use the Makefile in our CI tool, that inserts auto-increment numbers in place of git hashes. Numbers are a familiar. Ex: make VERSION_STRING=v%build.number%; make screener-d-debug VERSION_STRING=v%build.number%; Can i insert a version number when i run dub? You can do it by using `preBuildCommands` in dub.sdl, see http://code.dlang.org/package-format?lang=sdl How can i pass a VERSION_STRING from the cmd line? I don't know about passing from cli, but you can redirect output to some .d file and import it, for example.
encoding ISO-8859-1 to UTF-8 in std.net.curl
import std.stdio;
import std.net.curl;
void main()
{
string url = "www.site.ru/xml/api.asp";
string data =
"
59538
...
";
auto http = HTTP();
http.clearRequestHeaders();
http.addRequestHeader("Content-Type", "application/xml");
//Accept-Charset: utf-8
http.addRequestHeader("Accept-Charset", "utf-8");
//ISO-8859-1
//http://www.artlebedev.ru/tools/decoder/
//ISO-8859-1 → UTF-8
auto content = post(url, "data", http);
// content in ISO-8859-1 to UTF-8 encoding but I lose
//the Cyrillic "encoding='UTF-8'?>отсутствует или неверно задан параметр"
// I get it "encoding='UTF-8'?>оÑÑÑÑÑÑвÑÐµÑ Ð¸Ð»Ð¸ невеÑно
задан паÑамеÑÑ"
// How do I change the encoding to UTF-8 in response
string s = cast(immutable char[])content;
auto f = File("output.txt","w"); // output.txt file in UTF-8;
f.write(s);
f.close;
}
Re: How do i convert this Makefile to dub
On Monday, 8 August 2016 at 18:45:35 UTC, drug007 wrote: On 08.08.2016 21:35, Adil wrote: On Monday, 8 August 2016 at 18:29:54 UTC, Adil wrote: [...] One minor addition. I use the Makefile in our CI tool, that inserts auto-increment numbers in place of git hashes. Numbers are a familiar. Ex: make VERSION_STRING=v%build.number%; make screener-d-debug VERSION_STRING=v%build.number%; Can i insert a version number when i run dub? You can do it by using `preBuildCommands` in dub.sdl, see http://code.dlang.org/package-format?lang=sdl How can i pass a VERSION_STRING from the cmd line?
Re: How do i convert this Makefile to dub
On 08.08.2016 21:35, Adil wrote: On Monday, 8 August 2016 at 18:29:54 UTC, Adil wrote: I have a Makefile setup that I use to return the latest git tag/commit from within my program. The setup is as below: VERSIONED_LIB = myversion.d && rm -f myversion.d VERSION_STRING ?= $(shell git rev-parse --short HEAD) makeVersion: echo "module compileConfig; public string versionString = \"$(VERSION_STRING)\";" > myversion.d; mysoftware: makeVersion dmd -de -O /* compiler flags */ source/myprogrma.d myversion.d rm -f myversion.d When i run `make mysoftware` my binary now contains the latest git commit HASH, which i use for debugging. How can i mimic the same setup i dub? Is there an alternative to achieve the same goal? One minor addition. I use the Makefile in our CI tool, that inserts auto-increment numbers in place of git hashes. Numbers are a familiar. Ex: make VERSION_STRING=v%build.number%; make screener-d-debug VERSION_STRING=v%build.number%; Can i insert a version number when i run dub? You can do it by using `preBuildCommands` in dub.sdl, see http://code.dlang.org/package-format?lang=sdl
Re: How do i convert this Makefile to dub
On Monday, 8 August 2016 at 18:29:54 UTC, Adil wrote: I have a Makefile setup that I use to return the latest git tag/commit from within my program. The setup is as below: VERSIONED_LIB = myversion.d && rm -f myversion.d VERSION_STRING ?= $(shell git rev-parse --short HEAD) makeVersion: echo "module compileConfig; public string versionString = \"$(VERSION_STRING)\";" > myversion.d; mysoftware: makeVersion dmd -de -O /* compiler flags */ source/myprogrma.d myversion.d rm -f myversion.d When i run `make mysoftware` my binary now contains the latest git commit HASH, which i use for debugging. How can i mimic the same setup i dub? Is there an alternative to achieve the same goal? One minor addition. I use the Makefile in our CI tool, that inserts auto-increment numbers in place of git hashes. Numbers are a familiar. Ex: make VERSION_STRING=v%build.number%; make screener-d-debug VERSION_STRING=v%build.number%; Can i insert a version number when i run dub?
How do i convert this Makefile to dub
I have a Makefile setup that I use to return the latest git tag/commit from within my program. The setup is as below: VERSIONED_LIB = myversion.d && rm -f myversion.d VERSION_STRING ?= $(shell git rev-parse --short HEAD) makeVersion: echo "module compileConfig; public string versionString = \"$(VERSION_STRING)\";" > myversion.d; mysoftware: makeVersion dmd -de -O /* compiler flags */ source/myprogrma.d myversion.d rm -f myversion.d When i run `make mysoftware` my binary now contains the latest git commit HASH, which i use for debugging. How can i mimic the same setup i dub? Is there an alternative to achieve the same goal?
Re: string mixup problem with stdin.byLine
On Monday, 8 August 2016 at 07:09:55 UTC, torea wrote: On Monday, 8 August 2016 at 05:17:24 UTC, Dave Akers wrote: I do believe your problem is with the line... On Monday, 8 August 2016 at 02:44:20 UTC, torea wrote: string cleanLine = strip( cast(string)line ); It's casting a char[] to and immutable(char)[], causing the mutable buffer from byLine to be used as a string. what you want is... string cleanLine = strip( to!string(line) ); which should make a copy of the mutable buffer. I still a beginner at D but I think that will fix your problem. -Dave Problem fixed!! Thank you very much for the solution and the explanation! Alternatively you can use std.stdio.byLineCopy and don't need to add the `to!string`. If you are calling to!string on ever line there will probably be no performance difference, but if you are not, such as only calling to!string on every *second* line or something like that, you should stick with byLine and calling to!string when needed.
Re: string mixup problem with stdin.byLine
On Monday, 8 August 2016 at 07:09:55 UTC, torea wrote: On Monday, 8 August 2016 at 05:17:24 UTC, Dave Akers wrote: I do believe your problem is with the line... On Monday, 8 August 2016 at 02:44:20 UTC, torea wrote: string cleanLine = strip( cast(string)line ); It's casting a char[] to and immutable(char)[], causing the mutable buffer from byLine to be used as a string. what you want is... string cleanLine = strip( to!string(line) ); which should make a copy of the mutable buffer. I still a beginner at D but I think that will fix your problem. -Dave Problem fixed!! Thank you very much for the solution and the explanation! You should always carefully read the description and Notes ;-) Note: Each front will not persist after popFront is called, so the caller must copy its contents (e.g. by calling to!string) when retention is needed. If the caller needs to retain a copy of every line, use the byLineCopy function instead. http://dlang.org/phobos/std_stdio.html#.File.byLine Unfortunately you are not the first one who bumped into this problem and this non intuitive behavior of byLine is heavily disputed.
Re: method static-ness has no effect on the type?
On Monday, 8 August 2016 at 10:21:47 UTC, ag0aep6g wrote: Also thanks for submitting the bug for me.
Re: method static-ness has no effect on the type?
On 08/08/2016 12:14 PM, Cauterite wrote: On Monday, 8 August 2016 at 10:05:58 UTC, ag0aep6g wrote: The first assert compares the return types of f1 and f2. They both return `void`, so everything's fine there. I think you're mistaken about this. typeof(S.f1) definitely gives the type of the function, not of the return. Try it out: Yup. My mistake. It's the same as with & then.
Re: Question regarding Base64 decoding
Am 02.08.2016 um 00:47 schrieb Seb: > On Monday, 1 August 2016 at 08:53:30 UTC, Kagamin wrote: >> A bug. > > ... which should be filled at Bugzilla and/or fixed. Thanks! :) I created a pullrequest: https://github.com/dlang/phobos/pull/4720
Re: Cannot distinguish between template function wtih 0 args and 1 arg
On 08/08/2016 04:36 AM, Engine Machine wrote: This really makes no sense Error: template Mem cannot deduce function from argument types !(cast(eException)1280L, "main.d", 38u, "main.WinMain")(int), candidates are: Mem(T, B = eX, string file = __FILE__, uint line = __LINE__, string func = __FUNCTION__)(size_t bytes) Mem(T, B = eX, string file = __FILE__, uint line = __LINE__, string func = __FUNCTION__)() Going backwards: func is "main.Winmain" - ok. line is 38u - ok. file is "main.d" - ok. B is cast(eException)1280L - B seems to be a type parameter, can't be a value. T is missing. The compiler goes forwards, not backwards, of course, so everything is mismatched. [...] This only occurs when I call it with the non-default template values: I call it simply like Mem!(T, B, file, line, func)(34). That doesn't look like the instantiation that causes the error. You've got five template arguments here, but in the error there are only four. Can you post more complete code? Something doesn't add up here.
Re: method static-ness has no effect on the type?
On Monday, 8 August 2016 at 10:05:58 UTC, ag0aep6g wrote:
The first assert compares the return types of f1 and f2. They
both return `void`, so everything's fine there.
I think you're mistaken about this. typeof(S.f1) definitely gives
the type of the function, not of the return. Try it out:
struct S {
void f1(int, string, float) {};
};
static assert(typeof(S.f1).stringof == "void(int, string,
float)");
( https://dpaste.dzfl.pl/cda66002120a )
Re: method static-ness has no effect on the type?
On 08/08/2016 10:30 AM, Cauterite wrote:
See: https://dpaste.dzfl.pl/2ec6780d4b25
That code is short enough to post it here directly. For easier
reference, this is it:
struct S {
void f1() {
auto x =
};
static void f2() {
static assert(!__traits(compiles, {auto x = }));
};
};
static assert(is(typeof(S.f1) == typeof(S.f2))); // ?
static assert(is(typeof() == typeof())); // ?
static assert(!__traits(isStaticFunction, S.f1));
static assert(__traits(isStaticFunction, S.f2));
void main() {
// call f2;
S.init.f2();
// mov [ebp-4], S.init;
// lea eax, [ebp-4];
// call f1;
S.init.f1();
};
(Aside: no semicolons after function/struct declarations in D.)
We have two methods defined, f1 and f2, where f2 is static but they have
otherwise identical signatures.
We can see from the disassembly that f1 receives a `this` pointer while
f2 does not.
Yet, typeof() == typeof(). This makes no sense, how can the
compiler even know whether to pass a `this` pointer when both methods
have same type?
The first assert compares the return types of f1 and f2. They both
return `void`, so everything's fine there.
The second assert is a bit more surprising. `` is considered a
function, but `` is a delegate. Obviously, you can't get a
proper delegate from just the type. You need an instance of the struct
for that. So having `` be a delegate would be weird, too.
I don't know why `` is allowed at all. Maybe there is a good
reason, but it also allows bad stuff like this:
struct S
{
void f1(int x) { import std.stdio; writeln(x); }
}
void main()
{
void function(int x) f =
f(42); /* prints garbage */
}
This even works in @safe code. It also works when using .funcptr to get
the function pointer from a delegate. I'v filed an issue:
https://issues.dlang.org/show_bug.cgi?id=16365
Re: Tracking memory usage
On Sunday, 7 August 2016 at 00:28:40 UTC, Alfred Pincher wrote:
this is a very nice feature. I hope D has something similar?
If you want to implement that kind of allocation tracking you'll
probably want to use gc_getProxy()+gc_setProxy(). They're global
C functions you can access by declaring:
extern(C) gc.gcinterface.GC gc_getProxy() nothrow;
extern(C) void gc_setProxy(gc.gcinterface.GC);
First call gc_getProxy() to get the real GC instance and save it
somewhere.
Then call gc_setProxy() with your object implementing the GC
interface functions, and in each function forward to the
corresponding function of the real GC instance, after any
statistic-gathering code you want run.
Something like this:
__gshared GC RealGcInstance = gc_getProxy();
__gshared GC MyProxy = new class GC {
// ...
extern(C) void gc_free(void* Ptr) nothrow {
printf("freeing pointer %x\n", Ptr); // or whatever
return RealGcInstance.free(Ptr);
};
// ... etc.
};
gc_setProxy(MyProxy);
I haven't tested this method myself, but it will probably work.
Refer to
https://github.com/dlang/druntime/blob/master/src/gc/proxy.d and
https://github.com/dlang/druntime/blob/master/src/gc/gcinterface.d
Also remember that you can't invoke the GC from inside the proxy
functions. Using helper functions marked @nogc might make it
easier to avoid.
Re: callback craziness
On 08/08/2016 02:42 AM, Engine Machine wrote:
So, what about passing in the lambda verses the temp variable?
Nothing. I didn't see a case where it worked one way but not the other.
If you have code where adding a variable makes things work, please post
a complete test case.
[...]
My code is as follows and I cannot get 0 parameters working nor passing
the function in directly. These were my original questions to begin with
and haven't been answered. Here is the code I am using.
alias callback(Args...) = @nogc void function(string, int, Args);
@nogc public void foo(Args...)(callback!Args c, Args args, int x) { }
foo((string s, int i) { }, 1);
does not work
nor does
foo!()((string s, int i) { }, 1);
The second one does work. https://dpaste.dzfl.pl/212b467c62a4
Ultimately it would also be nice if the template parameters were deduced
automatically instead of having to specify them. The compiler should be
able to figure out the types supplied parameters.
e.g.,
foo((string s, int i, T x) { }, someT, 1);
instead of
foo!(T)((string s, int i, T x) { }, someT, 1);
should it not?
I think the `callback` template is the problem here.
Template instantiation is a one way street. You generally can't answer
the question "With what arguments would template Foo need to be
instantiated to get result Bar?". For starters, multiple different
arguments may map to the same result, making the reverse ambiguous.
It works when you skip the `callback` template and put the
function/delegate type directly into the signature:
@nogc public void foo(Args...)(void function(string, int, Args) @nogc c,
Args args, int x)
{}
void main() @nogc
{
foo((string s, int i) { }, 1);
alias T = float;
T someT;
foo((string s, int i, T x) { }, someT, 1);
}
method static-ness has no effect on the type?
See: https://dpaste.dzfl.pl/2ec6780d4b25 We have two methods defined, f1 and f2, where f2 is static but they have otherwise identical signatures. We can see from the disassembly that f1 receives a `this` pointer while f2 does not. Yet, typeof() == typeof(). This makes no sense, how can the compiler even know whether to pass a `this` pointer when both methods have same type?
Re: Cannot distinguish between template function wtih 0 args and 1 arg
On Monday, 8 August 2016 at 02:36:24 UTC, Engine Machine wrote: Error: template Mem cannot deduce function from argument types !(cast(eException)1280L, "main.d", 38u, "main.WinMain")(int), candidates are: Mem(T, B = eX, string file = __FILE__, uint line = __LINE__, string func = __FUNCTION__)(size_t bytes) Mem(T, B = eX, string file = __FILE__, uint line = __LINE__, string func = __FUNCTION__)() From this error message it looks like the `B = eX` parameter is not getting matched up against the value `cast(eException)1280L` as you are hoping for. Probably because `1280L` is a value and it's expecting a type. Try replacing it with something like `alias B = eX` or `enum B = eX`.
Re: string mixup problem with stdin.byLine
On Monday, 8 August 2016 at 05:17:24 UTC, Dave Akers wrote: I do believe your problem is with the line... On Monday, 8 August 2016 at 02:44:20 UTC, torea wrote: string cleanLine = strip( cast(string)line ); It's casting a char[] to and immutable(char)[], causing the mutable buffer from byLine to be used as a string. what you want is... string cleanLine = strip( to!string(line) ); which should make a copy of the mutable buffer. I still a beginner at D but I think that will fix your problem. -Dave Problem fixed!! Thank you very much for the solution and the explanation!
