should chain be pure

[Daniel Davidson]

On Tuesday, 15 October 2013 at 13:43:55 UTC, bearophile wrote:
> Daniel Davidson:
>
>> I would like to correctly annotate my functions with pure. 
>> I've hit a function that is calling chain which breaks purity. 
>> Is chain really not pure?
>
> Phobos is slowly being annotated with pure/nothrow (and @safe) 
> but not all functions are already tagged.
>
> You could fix the problem sending a Phobos patch.
>
> Bye,
> bearophile

That is probably beyond my pay-grade at the moment :-)

If I just add pure to chain and run unittests all sorts of errors 
cascade and I don't think I'm in a position to pull it off.

If you are agreeing that chain should be pure and it is just 
following all the calls and making all of them pure, until that 
happens by the professionals - is there a casting solution so I 
can fake a pure and move on?