[cmake-developers] A policy for Policies

[Stephen Kelly]

Brad King wrote:

> On 06/08/2015 04:15 PM, Stephen Kelly wrote:
>> This isn't a 3.3 feature but a change to the documentation/release notes
>> which is supposed to be ok?
> 
> Yes, if the wording does not commit us to a specific future release.

Even if the docs say 'the next release', we are not obligated to remove them 
in the next release.

>> I've changed the release notes to say 'some future release' instead. So,
>> we can figure that out on a per-Policy basis.
> 
> Okay.  Actually shouldn't the documentation of every policy say it may
> be removed in a future release?  

Yes. This documentation note is not necessary at all. The fact that they are 
Policies is already enough as you said.

I just added it for notification anyway because it's possible.

> That is their general purpose.  Perhaps
> that may help discourage projects from setting them to OLD.

 http://www.cmake.org/cmake/help/v3.2/manual/cmake-policies.7.html

 "The ``OLD`` behavior of each policy is undesirable and will be replaced 
 with an error condition in a future release."
 
Given what we see on mailing lists and SO, that doesn't help. 

In fact, I added that in response to someone on SO recommending setting 
policies to OLD and pointed them to the commit and the generated docs, and 
they're still recommending the same thing as SO answers. Policies are alive 
too long to be credible pending error-conditions. They look like - and are 
treated as - feature toggles.

Thanks,

Steve.