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digitalmars.D.learn - Static class question

reply Lubos Pintes <lubos.pintes gmail.com> writes:
Hi,
I saw one ListBox class implementation.
As we all know, ListBox class collects and displays strings. Author 
decided that he encapsulate the Object as item, and uses its toString() 
method when string is needed for display.
For cases when string is added, he defined this small class, internal to 
ListBox:
[code]
	private static class StringItem
	{
		private string _str;

		public this(string s)
		{
			this._str = s;
		}

		public override string toString()
		{
			return this._str;
		}
	}
[/code]

After I read about attributes on dlang, I think the static could be 
removed from above definition. Is this true?
Thank
Feb 14 2013
parent "anonymous" <anonymous example.com> writes:
On Thursday, 14 February 2013 at 12:49:01 UTC, Lubos Pintes wrote:

 Hi,
 I saw one ListBox class implementation.
 As we all know, ListBox class collects and displays strings. 
 Author decided that he encapsulate the Object as item, and uses 
 its toString() method when string is needed for display.
 For cases when string is added, he defined this small class, 
 internal to ListBox:
 [code]
 	private static class StringItem
 	{
 		private string _str;

 		public this(string s)
 		{
 			this._str = s;
 		}

 		public override string toString()
 		{
 			return this._str;
 		}
 	}
 [/code]

 After I read about attributes on dlang, I think the static 
 could be removed from above definition. Is this true?
 Thank


Without 'static', StringItem objects would be tied to ListBox
objects. 'static' saves StringItem objects some bytes, and
ensures that StringItem is independent of ListBox.
See http://dlang.org/class.html#nested
Feb 14 2013