Talk:Covariance and generics case study - Revision history

Clemahieu at 17:26, 3 July 2008

2008-07-03T17:26:05Z

Clemahieu at 15:38, 21 April 2008

2008-04-21T15:38:41Z

Peter gummer at 00:53, 14 April 2008

2008-04-14T00:53:15Z

New page

--[[User:Peter gummer|Peter gummer]] 17:53, 13 April 2008 (PDT)
This is a really good comparison!

The explosion of complex declarations in the generic cases could be defused by declaring new classes. It's similar to how you had to declare new classes to redefine features covariantly. Those new classes would encapsulate the generic parameters, saving clients the trouble of worrying about the generics.

← Older revision		Revision as of 17:26, 3 July 2008
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	----		----
	I tried doing this and it worked well for routine parameters but broke down with function returns. The functions wanted to return the complex generic class but I couldn't downcast these to the simplified versions.		I tried doing this and it worked well for routine parameters but broke down with function returns. The functions wanted to return the complex generic class but I couldn't downcast these to the simplified versions.
		+
		+
		+	----
		+
		+	For example if I had a class operating on complex generic parameters:
		+
		+	class SIMPLE
		+	inherit (complex generic type)
		+
		+	encrypt (in: (complex generic type))
		+	is do end
		+
		+	make_new_key: (complex generic type)
		+	is do end
		+
		+	I could put SIMPLE in to the encrypt feature, however, I could not assign the return from make_new_key to SIMPLE.

← Older revision		Revision as of 15:38, 21 April 2008
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	The explosion of complex declarations in the generic cases could be defused by declaring new classes. It's similar to how you had to declare new classes to redefine features covariantly. Those new classes would encapsulate the generic parameters, saving clients the trouble of worrying about the generics.		The explosion of complex declarations in the generic cases could be defused by declaring new classes. It's similar to how you had to declare new classes to redefine features covariantly. Those new classes would encapsulate the generic parameters, saving clients the trouble of worrying about the generics.
		+
		+
		+	----
		+	I tried doing this and it worked well for routine parameters but broke down with function returns. The functions wanted to return the complex generic class but I couldn't downcast these to the simplified versions.