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digitalmars.D.learn - How does one correct shadowing (hidden by) errors?

reply "Tyro[a.c.edwards]" <nospam home.com> writes:
While attempting to build the DFL libraries, I encountered the following 
three errors:

[1] tabcontrol.d(18): Error: class dfl.tabcontrol.TabPage use of 
dfl.control.Control.opEquals(Control ctrl) hidden by TabPage is deprecated

[2] tabcontrol.d(18): Error: class dfl.tabcontrol.TabPage use of 
dfl.control.Control.opCmp(Control ctrl) hidden by TabPage is deprecated

[3] imagelist.d(22): Error: class 
dfl.imagelist.ImageList.ImageCollection use of 
dfl.imagelist.ImageList.ImageCollection.ListWrapArray!(Image,_images,_adding,_added,_blankListCallback,_removed,false,fal
e,false).insert(int 
index, Image value) hidden by ImageCollection is deprecated

Now I know I can bypass this with the -d switch but I'm more interested 
in fixing the problem than bypassing it.

Control defines the following two functions:

	override Dequ opEquals(Object o)
	{
		Control ctrl = cast(Control)o;
		if(!ctrl)
			return 0; // Not equal.
		return opEquals(ctrl);
	}

	override int opCmp(Object o)
	{
		Control ctrl = cast(Control)o;
		if(!ctrl)
			return -1;
		return opCmp(ctrl);
	}
	
Whereas TabPage defines the following:

	override Dequ opEquals(Object o)
	{
		return text == getObjectString(o);
	}

	override int opCmp(Object o)
	{
		return stringICmp(text, getObjectString(o));
	}

How does one correct this such that the latter does not hide the first?

Problem [3] on the other hand is caused by a template mixin in the 
dfl.imagelist.ImageList.ImageCollection. ImageCollection is not a 
derived class so I do not understand what is being hidden. Please 
explain. Also, a suggestion on how to correct the issue would be 
helpful. The code is as follows:

class ImageList
{
	class ImageCollection
	{
		...
		public:
		mixin ListWrapArray!(Image, _images,
			_adding, _added,
			_blankListCallback!(Image), _removed,
			false, false, false);
	}
	...
}

Thanks
Jul 22 2011
next sibling parent reply Andrej Mitrovic <andrej.mitrovich gmail.com> writes:
I'm not sure about the issue, but just in case it's not known the
newest DFL seems to be hosted on github: https://github.com/Rayerd/dfl

It might have those issues fixed, unless this is where you've cloned
from, in which case sorry for the noise.
Jul 22 2011
parent reply Jesse Phillips <jessekphillips+d gmail.com> writes:
On Sat, 23 Jul 2011 08:34:27 +0200, Andrej Mitrovic wrote:


 I'm not sure about the issue, but just in case it's not known the newest
 DFL seems to be hosted on github: https://github.com/Rayerd/dfl
 
 It might have those issues fixed, unless this is where you've cloned
 from, in which case sorry for the noise.


It is not fixed there, it is missing a number of changes. This is one of 
them and I'm confused on since I thought override was supposed to, well 
override.
Jul 23 2011
parent reply bearophile <bearophileHUGS lycos.com> writes:
Jesse Phillips:


 It is not fixed there, it is missing a number of changes. This is one of 
 them and I'm confused on since I thought override was supposed to, well 
 override.


I think we are talking about two different things: overriding and overloading.

Bye,
bearophile
Jul 23 2011
parent Jesse Phillips <jessekphillips+d gmail.com> writes:
On Sat, 23 Jul 2011 10:51:35 -0400, bearophile wrote:


 Jesse Phillips:
 

 It is not fixed there, it is missing a number of changes. This is one
 of them and I'm confused on since I thought override was supposed to,
 well override.


 
 I think we are talking about two different things: overriding and
 overloading.
 
 Bye,
 bearophile


Ok, I got it. The problem is not overriding ALL the opEquals functions in 
the child class. I.e. you must override all overloaded functions when 
overriding one function.
Jul 23 2011
prev sibling parent reply bearophile <bearophileHUGS lycos.com> writes:
Tyro[a.c.edwards]:


 [3] imagelist.d(22): Error: class 
 dfl.imagelist.ImageList.ImageCollection use of 
 dfl.imagelist.ImageList.ImageCollection.ListWrapArray!(Image,_images,_adding,_added,_blankListCallback,_removed,false,fal
e,false).insert(int 
 index, Image value) hidden by ImageCollection is deprecated
 
 Now I know I can bypass this with the -d switch but I'm more interested 
 in fixing the problem than bypassing it.


There is a trick based on explicit alias to avoid those errors. I'd like the
idea of using this alias to be present in that error message...

Bye,
bearophile
Jul 23 2011
next sibling parent reply "Tyro[a.c.edwards]" <nospam home.com> writes:
On 7/23/2011 7:49 PM, bearophile wrote:

 Tyro[a.c.edwards]:


 [3] imagelist.d(22): Error: class
 dfl.imagelist.ImageList.ImageCollection use of
 dfl.imagelist.ImageList.ImageCollection.ListWrapArray!(Image,_images,_adding,_added,_blankListCallback,_removed,false,false,false).insert(int
 index, Image value) hidden by ImageCollection is deprecated

 Now I know I can bypass this with the -d switch but I'm more interested
 in fixing the problem than bypassing it.


 There is a trick based on explicit alias to avoid those errors. I'd like the
idea of using this alias to be present in that error message...

 Bye,
 bearophile


Please do share. I thought the concept explicit alias simply requires me 
to do his:

alias ListWrapArray LWA;
mixin LWA!(Image, _images,
	_adding, _added,
	_blankListCallback!(Image), _removed,
	false, false, false);

This did not work... resulted in the same error. On closer look it seems 
the actual problem is not the template but the definition of "insert" 
therein. It is being hidden by the definition of insert in ImageCollection.

ImageCollection definition:

	void insert(int index, Image img)
	{
		if(index >= _images.length)
		{
			add(img);
		}
		else
		{
			assert(0, "Must add images to the end of the image list");
		}
	}

ListWrapArray definition:

	void insert(int index, TValue value)
	{
		_insert(index, value);
	}

In the end it turns out to be the same problem as one and two. Any 
suggestion on how to deal with these correctly? I can resolve this 
particular error by renaming the function to "Insert" in 
ImageCollection. But even though it appeases the compiler, is that the 
correct solution? Is there something else that I'm not taking into 
consideration? How do I fix the other two since there is no way to 
rename opApply and opCmp that I'm aware of?

Thanks
Jul 23 2011
parent bearophile <bearophileHUGS lycos.com> writes:
Tyro[a.c.edwards]:


 Please do share. I thought the concept explicit alias simply requires me 
 to do his:


I meant this, but I don't know if this is enough to solve your problem:
http://www.digitalmars.com/d/archives/digitalmars/D/learn/class_x_is_hidden_by_y_22131.html

Bye,
bearophile
Jul 24 2011
prev sibling parent bearophile <bearophileHUGS lycos.com> writes:
 There is a trick based on explicit alias to avoid those errors. I'd like the
idea of using this alias to be present in that error message...


http://d.puremagic.com/issues/show_bug.cgi?id=6373

Bye,
bearophile
Jul 24 2011