On Friday, 9 January 2015 at 13:01:14 UTC, Steven Schveighoffer
wrote:
On 1/9/15 7:47 AM, Daniel Kozák via Digitalmars-d wrote:
V Fri, 09 Jan 2015 07:21:02 -0500
Steven Schveighoffer via Digitalmars-d
<digitalmars-d@puremagic.com>
napsáno:
On 1/9/15 6:57 AM, Daniel Kozak wrote:
I often have code like this:
class A {
final:
nothrow:
...
some methods
...
}
Problem comes when I need add methods which for eg.: throws
or need
to be virtual.
I can put them before final: but this is not perfect,
because I
prefer when methods are place in specific order (method abc
call
method asd so asd is bellow abc and so on).
So today I download dmd source and make some small
modification
(only few lines) and this is the result:
http://dpaste.dzfl.pl/472afc938397
Nice, but I don't like the fact that it bluntly returns all
attributes to default.
For example, if you need to remove the final attribute, but
not
nothrow, I'm assuming it looks something like:
default nothrow void foo()
which doesn't read very well.
If we are going to do this, I'd rather see something like has
been
suggested before -- parameterizing attributes:
final(false) -> remove final
This allows compile-time booleans to modify attributes in
ways that
are extremely difficult in templates today.
I think both ways shoud be available
when I need remove just one attr than attr!false is nice but
when I
need remove for eg: 3 or more it will look like:
void someFunc final(false) pure(false) nothrow(false)
in this case I think that:
default void foo() nothrow looks OK now :)
I'd rather combine the parameterization with attribute sets
(i.e. aliasing sets of attributes to one symbol). The 'default'
idea is ok, but I think it's too clever -- the word "default"
doesn't immediately say "attributes", so it's going to confuse
people.
-Steve
It could work both ways at the same time.
Maybe even something like "default(pred) final(pred) nothrow" -->
if pred is compile-time-true, reset all attributes and then add
final/nothrow; if it's compile-time-false, disable final and
enable nothrow.
