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digitalmars.D.learn - UFCS from within classes

reply "Gyron" <Threk web.de> writes:
Hey there, I've experimented a little with UFCS today and ran 
into a problem.

My first question, which is kinda off-topic:
Why does D use the int type if you give it a number started with 
0x(hex), shouldn't it use uint for that ?

Here comes the real question:
I've extended the int by one function, which is the following 
(just to represent the problem):
public static T read(T)(int address)
{
	return cast(T)1;
}

It works perfectly if the function stands alone (is global), but 
it doesn't work if I put it into a class (because I want it to be 
a bit more organized) like that:
class CMemory
{
	public static T read(T)(int address)
	{
		return cast(T)1;
	}
}

I'm not able to write something like:
0x1212.CMemory.read!bool();


So the question is, how can I make it to be able to be used like 
this:
0x1212.read!bool();

but still organized within the class ?
Sep 09 2013
next sibling parent reply "H. S. Teoh" <hsteoh quickfur.ath.cx> writes:
On Mon, Sep 09, 2013 at 07:07:58PM +0200, Gyron wrote:

 Hey there, I've experimented a little with UFCS today and ran into a
 problem.
 
 My first question, which is kinda off-topic:
 Why does D use the int type if you give it a number started with
 0x(hex), shouldn't it use uint for that ?


Good point, please file a bug on: http://d.puremagic.com/issues



 Here comes the real question:
 I've extended the int by one function, which is the following (just
 to represent the problem):
 public static T read(T)(int address)
 {
 	return cast(T)1;
 }
 
 It works perfectly if the function stands alone (is global), but it
 doesn't work if I put it into a class (because I want it to be a bit
 more organized) like that:
 class CMemory
 {
 	public static T read(T)(int address)
 	{
 		return cast(T)1;
 	}
 }
 
 I'm not able to write something like:
 0x1212.CMemory.read!bool();
 
 
 So the question is, how can I make it to be able to be used like
 this:
 0x1212.read!bool();
 
 but still organized within the class ?


I don't think UFCS works with qualified names right now. This is a known
issue. The best way to solve this problem is to put your function in a
separate module instead of a class, then importing the module will pull
it into your current namespace and you can use it as above, yet have it
organized by module (but not by class -- that's unfortunately not
possible right now). Something like this:

	----memory.d----
	module memory;
	T read(T)(int address) { ... }

	----main.d----
	import memory;
	void main() {
		0x1212.read!bool();
	}


T

-- 
Shin: (n.) A device for finding furniture in the dark.
Sep 09 2013
next sibling parent "Gyron" <Threk web.de> writes:
On Monday, 9 September 2013 at 17:17:07 UTC, H. S. Teoh wrote:

 On Mon, Sep 09, 2013 at 07:07:58PM +0200, Gyron wrote:

 Hey there, I've experimented a little with UFCS today and ran 
 into a
 problem.
 
 My first question, which is kinda off-topic:
 Why does D use the int type if you give it a number started 
 with
 0x(hex), shouldn't it use uint for that ?


 Good point, please file a bug on: http://d.puremagic.com/issues



 Here comes the real question:
 I've extended the int by one function, which is the following 
 (just
 to represent the problem):
 public static T read(T)(int address)
 {
 	return cast(T)1;
 }
 
 It works perfectly if the function stands alone (is global), 
 but it
 doesn't work if I put it into a class (because I want it to be 
 a bit
 more organized) like that:
 class CMemory
 {
 	public static T read(T)(int address)
 	{
 		return cast(T)1;
 	}
 }
 
 I'm not able to write something like:
 0x1212.CMemory.read!bool();
 
 
 So the question is, how can I make it to be able to be used 
 like
 this:
 0x1212.read!bool();
 
 but still organized within the class ?


 I don't think UFCS works with qualified names right now. This 
 is a known
 issue. The best way to solve this problem is to put your 
 function in a
 separate module instead of a class, then importing the module 
 will pull
 it into your current namespace and you can use it as above, yet 
 have it
 organized by module (but not by class -- that's unfortunately 
 not
 possible right now). Something like this:

 	----memory.d----
 	module memory;
 	T read(T)(int address) { ... }

 	----main.d----
 	import memory;
 	void main() {
 		0x1212.read!bool();
 	}


 T


The thing is, that I already have other classes in that module 
and I hate to mix global functions(global in the means of global 
in the module) with classes.
I would separate them in different files, but sadly thats not 
possible (as far as I can see, because you can only define the 
module once, not like namespaces in c++).
Sep 09 2013
prev sibling parent Jacob Carlborg <doob me.com> writes:
On 2013-09-09 19:15, H. S. Teoh wrote:


 I don't think UFCS works with qualified names right now. This is a known
 issue.


As far as I know it's a design decision.

-- 
/Jacob Carlborg
Sep 09 2013
prev sibling parent "Maxim Fomin" <maxim maxim-fomin.ru> writes:
On Monday, 9 September 2013 at 17:07:59 UTC, Gyron wrote:

 Hey there, I've experimented a little with UFCS today and ran 
 into a problem.

 My first question, which is kinda off-topic:
 Why does D use the int type if you give it a number started 
 with 0x(hex), shouldn't it use uint for that ?


It is not a bug, but a feature - see Decimal Literal Types table 
at http://dlang.org/lex.html


 Here comes the real question:
 I've extended the int by one function, which is the following 
 (just to represent the problem):
 public static T read(T)(int address)
 {
 	return cast(T)1;
 }

 It works perfectly if the function stands alone (is global), 
 but it doesn't work if I put it into a class (because I want it 
 to be a bit more organized) like that:
 class CMemory
 {
 	public static T read(T)(int address)
 	{
 		return cast(T)1;
 	}
 }

 I'm not able to write something like:
 0x1212.CMemory.read!bool();


 So the question is, how can I make it to be able to be used 
 like this:
 0x1212.read!bool();

 but still organized within the class ?


class CMemory
{
         public static T read(T)(int address)
         {
                 return cast(T)1;
         }
}

alias CMemory.read!int CMread;

void main()
{
	 0.CMread();
}

You can also use alias CMemory.read CMread; plus 0.CMread!int();
Sep 09 2013