Make const, immutable, inout, and shared illegal as function attributes on the left-hand side of a function

[Joseph Rushton Wakeling via Digitalmars-d]

On Sunday, 12 October 2014 at 18:47:31 UTC, Walter Bright wrote:
> Deprecation is a way station on the way to removal. Warnings 
> are not necessarily headed that way.

Indeed, but the choice of _when_ to remove can in practice be 
quite free, no?  It would be possible to put in place this 
deprecation warning and wait for years before acting on it.