On Wednesday, 17 April 2013 at 23:46:08 UTC, Walter Bright wrote:
On 4/17/2013 3:20 PM, Timon Gehr wrote:
"This is the same issue as defining a function with 'auto' in
one place
and referring to it having a specific type/attribute in
another. So I
think all the same arguments and reasoning discussed above
apply equally."
Why is this a valid form of reasoning? The signature of a
function that has its
return type inferred includes the function body.
Furthermore, it is not the same issue. It is the dual issue.
The distinction is
very relevant because pure and nothrow are designed in an
asymmetric way,
They are the same - adding the attribute retains covariance.
No : if a super function suddenly become pure because its
implementation changed, then all kind of subclasses can broke.
Generally, it is a bad idea for a super class to be aware of its
subclasses.
But defining a function that is going to be overridden as auto is
asking for trouble in the first place.
