small idea

[eles]

On Wednesday, 9 January 2013 at 15:43:09 UTC, bearophile wrote:
> Tim Krimm:
>
>> Why make it a requirement or give a warning.
>
> If it's not enforced I think it becomes a not useful enough 
> feature.

Let's cut it at half: if "inout" &co. are specified, then 
non-concordance with function declaration will be a requirement.

If "inout" & co. are not specified, then they are simply not 
required. Code breakage will be avoided.