[MPEG-OTSPEC] Introducing breaking changes into the spec (was: RE: [EXTERNAL] Proposal to deprecate derived search values)

[David Singer]

> On Sep 11, 2020, at 14:14 , Adam Twardoch (Lists) <list.adam at twardoch.com> wrote:
> 
> Right now am implementer of OT 1.8 has to implement support for all six versions of the OS/2 table. OFF2 could get rid of that burden. 

This is probably a blindingly obvious statement, but a common technique is to differentiate the requirements for readers and creators, e.g. writers must write version 6 as the default, and may write other versions on request; readers must accept version 6, and should accept 3,4,5, and may accept earlier versions (the last doesn’t need saying, of course, people always may do anything above what the specs mandates or recommends).


David Singer
Manager, Software Standards, Apple Inc.