On 02/29/2012 09:30 PM, Stewart Gordon wrote:
On 29/02/2012 19:24, Timon Gehr wrote:
<snip>
That was just for documentation... The part that is explicit is:
// Single inheritance of state
class ExtendedWidget : Widget {
override void print(uint level)
in { /* weakening precondition is okay */ } body {
... level may be 0 here ...
}
}
The fact that this weakens the precondition tells us that it was not
weakened before.
Of course. I see now.
OK.
Besides, the interface declaration there isn't allowed by the grammar.
The compiler implements it.
So what? It's a bug that compiler behaviour doesn't match the
documentation. You seem to be agreed that this is the case with what
happens to the contract where the override has no InStatement at all.
I think in this case the documentation has not been updated yet because
the feature is still experimental. Anyway, even with the documentation,
many essential parts of the language are documented only on this
newsgroup or through the compiler implementation, unspecified completely
or only partly specified. I don't think it is currently possible to
become completely proficient in D without reading this newsgroup.
<snip>
So you consider illegal inputs to a function to be part of the API?
Yes. Put differently, I consider legal inputs to a overridable virtual
function to be part
of the API.
That legal inputs are part of the API is something we're agreed on. It's
illegal inputs we were debating.
But I can see what you really mean: the spec of what inputs to an
overridable function are legal and what inputs are illegal is part of
the API.
Stewart.
An input that is not legal is illegal and vice-versa.
