On 2012-02-17 04:15, H. S. Teoh wrote:
On Thu, Feb 16, 2012 at 06:49:40PM -0800, Walter Bright wrote:
[...]
So it occurred to me that an overriding function could *inherit* the
qualifiers from the overridden function. The qualifiers of the
overriding function would be the "tightest" of its explicit qualifiers
and its overridden function qualifiers. It turns out that most
functions are naturally pure, so this greatly eases things and
eliminates annoying typing.
I like this idea.
I want do to this for @safe, pure, nothrow, and even const.
Excellent!
I think it is semantically sound, as well. The overriding function
body will be semantically checked against this tightest set of
qualifiers.
What do you think?
Semantically, it makes sense. And reducing typing is always good.
(That's one of my pet peeves about Java: too much typing just to achieve
something really simple. It feels like being forced to kill a mosquito
with a laser-guided missile by specifying 3D coordinates accurate to 10
decimal places.)
The one disadvantage I can think of is that it will no longer be clear
exactly what qualifiers are in effect just by looking at the function
definition in a derived class. Which is not terrible, I suppose, but I
can see how it might get annoying if you have to trace the overrides all
the way up the inheritance hierarchy just to find out what qualifiers a
function actually has.
OTOH, if ddoc could automatically fill in the effective qualifiers, then
this will be a non-problem. ;-)
And if ddoc could show the inheritance hierarchy as well.
--
/Jacob Carlborg
