Is unix time function in wrong module?
Hi, shouldn't the unix time functions be in std.datetime.Date and std.datetime.DateTime instead of std.datetime.SysTime? The documentation states: - "std.datetime.systime for a point in time with a timezone." - "std.datetime.date for points in time without timezones." Unix epoch is 00:00:00 UTC on 1 January 1970 - and UTC is a standard, not a timezone. if i am not mistaken timezones getting applied on UTC - so i do not understand why the unix time functions are in the modules which are "timezone aware" and not in the modules without a timezone awareness.
Re: How do I create classes dynamically?
On Wednesday, 14 April 2021 at 20:38:16 UTC, Mario wrote: I wanted to find out if it is possible to create classes dynamically. out of curiosity: Why you would like to do this? I cannot think of a use case for this - this is why i ask.
null and initialized string comparisons
Hi, is this how it supposed to be? (https://run.dlang.io/is/7B4irm) --- string a = null; string t = ""; assert( ! a ); assert( t ); assert( t == a ); --- I have not expected assert(t == a) to be true - i would like to know the argument for why this is correct when at the same time assert(!a) and assert(t) is true.. feels a litle bit js-ish to me
Tuple or struct as return type?
Hi, lets say i want to create a function that returns multiple values - e.g. Tuple!(string,string). Why/when i should prefer Tuple as a return type over returning a struct (or even string[2] in this case)? Thank you
Re: why is "hello".writeln considered bad?
On Friday, 20 November 2020 at 10:03:18 UTC, Daniel Kozak wrote: I remember days when I liked UFCS too . Unfortunately it is not so awesome when you use it with IDE. And I would like to add: if you use in a bigger team. It's annoying when every dev have a own taste.. And together with optional () it's hell - no joke. The need to think about codeatyle definitions in such detail is a nogo for big projects.
Re: magically a static member on init?
On Sunday, 15 November 2020 at 00:29:41 UTC, H. S. Teoh wrote: if you don't like the semantics, don't use it; always allocate the field in the class ctor instead. Hi, i neither like it nor dislike it - it just caught me by surprise because i was under the impression that if i create a new instance then all members get initialized according to the declared optional default value. I can see how this is a feature - but it is also of kind "expert knowledge" and i would argue that "expert knowladge" is a designs arch enemy.
Re: magically a static member on init?
On Saturday, 14 November 2020 at 23:30:58 UTC, Adam D. Ruppe wrote: On Saturday, 14 November 2020 at 23:20:55 UTC, Martin wrote: Is this intentional? [...] alright, thank you! :)
magically a static member on init?
Hi, i do no know if this is intended - but imo this is weird: https://run.dlang.io/is/eBje3A I expected that `c.a.str == ""` (just like `c.str` is). But instead `c.a.str` keeps the value of `b.a.str`. Is this intentional? IMO this feels not consistent and its weird when a reference leaks into another instance without having declared it static member. Greetigs
Re: vibe.d / experience / feedback
On Friday, 2 October 2020 at 09:46:09 UTC, Denis Feklushkin wrote: Because standard implementation worse? What do you mean with "worse"? In my experience std.json is a very thin implementation of the JSON spec - without/very low "magic". IMO this is what one wants in a std lib. Its a good starting point for further simplfication wrappers or framework specific magic (what vibe actually do, if i am not mistaken
passing a parrameter read-only ref?
Hi, i would like to create a function which takes the first parameter as a reference to a struct - but assure the calle that the reference is read-only. Can this be done? If i am not mistaken, then the "in" Parameter Storage Class is what i want(?). But the documentation states that this feature should not be used. For context: I want to write struct-methods outside the struct (like in golang).
Re: How to compile Windows exe files from this source
On Sunday, 9 August 2020 at 19:04:07 UTC, Marc wrote: I don't know much more about D than creating a 'hello world' exe file with the DMD Compiler but I'm interested in using the eBay/tsv-utils binaries. Unfortunately, the author didn't create any MS Windows binaries: https://github.com/eBay/tsv-utils/releases Does anyone know how to compile this code into MS Windows binaries? It is a bit off-topic but I strongly suggest that you take a look at the windows subsystem for Linux, that is a on-board feature in Windows 10 (https://www.microsoft.com/en-us/p/ubuntu/9nblggh4msv6?activetab=pivot:overviewtab) It makes working with tools like tsvutils much more effective.
Re: Factory pattern for classes
On Sunday, 9 August 2020 at 15:56:31 UTC, Ali Çehreli wrote:
module deneme;
import std.stdio;
interface I {
void methodName();
}
...
I getClassById(uint id)
{
if (id == 0) {
return cast(A)Object.factory("deneme.A");
} else if(id == 1) {
return cast(B)Object.factory("deneme.B");
} else {
return cast(C)Object.factory("deneme.C");
}
}
void main() {
auto o = getClassById(1);
o.methodName();
}
Why not simply do?
I getClassById(uint id)
{
if (id == 0) {
return new A();
} else if(id == 1) {
return new B();
} else {
return new C();
}
}
Then you can also pass parameters to the constructors or call
further factories to create them, as long as they return a
`I`-compatible type.
Re: Polymorphism? Passing arguments
ok, thanks you very much for the information.
Re: Polymorphism? Passing arguments
Thank you for the answer
On Saturday, 4 November 2017 at 01:35:41 UTC, Adam D. Ruppe wrote:
Why are these ref?
Just taking ref away from both of those will likely fix your
problems.
because without it i get the error "Program exited with code -11"
The thing is, somwhere deeper in `setRelation` i call two
functions:
```
public void addChild(ref Node child) {
this.children ~=
}
public void setParent(ref Node parent) {
this.parent =
}
```
Polymorphism? Passing arguments
I have a interface
`interface Node {...}`
and some classes implementing Node:
```
class Text : Node {...}
class Element : Node {...}
```
and a function like this:
`public void setRelation(ref Node parent , ref Node child) {...}`
if i do this it works:
```
Node root = new Element("root");
Node text = new Text("blah");
setRelation(root , text);
```
but this does not:
```
Node root = new Element("root");
setRelation(root , new Text("blah"));
```
Error: function Nodes.setRelation (ref Node parent, ref Node
child) is not callable using argument types (Node, Text)
Why is this? Text implements Node. This is how i do it in other
Languages - How can would be this possible in D?
how to harvest the results of tasks from a taskpool?
Hi,
i have a coulpe of different machines with MySQL Servers running
on it.
Now, i want to execute queries for all Databases at the same time
and collect the Result to process it.
I am new to the parallelism - so maybe i understand something
totaly wrong.
What i tring is something like this:
{
auto tPool = new TaskPool();
forach(server ; servers)
{
auto task = task!queryWorker(query);
tPool.put(task);
}
tPool.finish(true);
//> how to collect the results now? <---
}
row[] queryWorker(string query) {
//rows = result of the query
return rows;
}
btw.. how to markup code in this forum?
Tuple/Typedef question
Is there a way to get Tuple (and Typedef) from the std.typecons module to generate a new type that is unique on every instantiation? What I mean is: alias T1 = Tuple!(int, int); alias T2 = Tuple!(int, int); writeln(__traits(isSame, T1, T2)); // prints true When using Typedef, the types are still the same: alias T1New = Typedef!(T1); alias T2New = Typedef!(T2); writeln(__traits(isSame, T1New, T2New)); // still prints true The documentation of Typedef says: Typedef allows the creation of a unique type which is based on an existing type. Unlike the alias feature, Typedef ensures the two types are not considered as equals. Shouldn't the second part at least print false then?
Re: Tuple/Typedef question
On Sunday, 11 January 2015 at 11:52:42 UTC, ketmar via Digitalmars-d-learn wrote: On Sun, 11 Jan 2015 11:41:08 + Martin via Digitalmars-d-learn digitalmars-d-learn@puremagic.com wrote: Is there a way to get Tuple (and Typedef) from the std.typecons module to generate a new type that is unique on every instantiation? What I mean is: alias T1 = Tuple!(int, int); alias T2 = Tuple!(int, int); writeln(__traits(isSame, T1, T2)); // prints true When using Typedef, the types are still the same: alias T1New = Typedef!(T1); alias T2New = Typedef!(T2); writeln(__traits(isSame, T1New, T2New)); // still prints true The documentation of Typedef says: Typedef allows the creation of a unique type which is based on an existing type. Unlike the alias feature, Typedef ensures the two types are not considered as equals. Shouldn't the second part at least print false then? as for `Typedef!` -- you can use it's third arg, cookie: import std.typecons; alias T1 = Tuple!(int, int); alias T2 = Tuple!(int, int); alias T1New = Typedef!(T1, T1.init, t0); alias T2New = Typedef!(T2, T2.init, t1); pragma(msg, __traits(isSame, T1New, T2New)); // false there was a heated discussion about `std.typecons.Typedef`, built-in `typedef` and other related things, but the decision was to keep the status quo. I can't believe I missed the cookie part. Thanks!
spawnProcess command-line arguments help
When I use the spawnProcess function in std.process, the command line arguments that I provide to the function seem to get quoted. Is there a way to tell the spawnProcess function that I want the command line arguments to be non-quoted? Example: spawnProcess([SomePath\\Test.exe], [-silent]); and the command line becomes: SomePath\Test.exe -silent (with the quotes exaclt like shown). Unfortunately (for some strange reason), the spawned process only responds to non-quoted arguments passed through the command line. So the command line should be exactly: SomePath\Test.exe -silent Is there any way to achieve this?
