Revert attributes to their defaults with default keywords

[Steven Schveighoffer via Digitalmars-d]

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 at 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