Thank you for the explanation. The following note should find it's way
into the class comment.

<note>

How are selectors ending with something like

         ttfclpomsswfpp0

constructed and what does it mean?


Answer:
​It is the initials of all instance variables followed by the class
version integer. The initials allow to detect  most changes to the
instance variables, but if this is not sufficient (perhaps because the
new var had the same initial, or the vars did not change in name at
all) we still have the class version.

Most classes are still at version 0, but if you check implementers of
classVersion you can find a few that were incremented to force a
conversion on load.

</note>

On 10/14/17, Bert Freudenberg <bert at freudenbergs.de> wrote:
> On Sat, Oct 14, 2017 at 11:37 AM, H. Hirzel <hannes.hirzel at gmail.com>
> wrote:
>
>> An explanation where and how
>>
>>      ttfclpomsswfpp0
>>
>> is constructed.
>
>
> ​It's the initials of all instance variables followed by the class version
> integer. The initials allow to detect  most changes to the instance
> variables, but if this is not sufficient (perhaps because the new var had
> the same initial, or the vars did not change in name at all) we still have
> the class version.
>
> Most classes are still at version 0, but if you check implementers
> of classVersion you can find a few that were incremented to force a
> conversion on load.
>
> - Bert -​
>