Re: 7.0 wishlist?

Joshua Cranmer <Pidgeot18@xxxxxxxxxxxxxxx> wrote:
Andreas Leitgeb wrote:
Joshua Cranmer <Pidgeot18@xxxxxxxxxxxxxxx> wrote:
Note, for example, that making a Square class extend a Rectangle
[...] would fail to match the Rectangle's contract.
what type of rectangle-related contract do you have in mind?
I hope it is not something like "width!=height must be allowed"
[example snipped, as it boiled down to exactly my prognose]

Whether Square breaks Rectangle's contracts of course depends on the
contracts put up by Rectangle. If it contains goofy contracts then,
indeed, Square may not match those.

The idea that changing the height does not change the width is what is
violated.
And that is, what I consider an #1 example of a goofy contract.

PS: but then again, the Square could override setWidth and setHeight
to throw a certain exception and instead offer a setSize...
The Rectangle class would have to "allow" the throwing of exceptions
in its contract for that.
.

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