On Thu, 23 Mar 2017 11:23:27 +0100 Otto Stolz <otto.st...@uni-konstanz.de> wrote:
> Same issue as with German sharp S: The blackletter »ß« derives from an > ſ-z ligature (thence its German name »Eszet«), whilst the Roman type > »ß« derives from an ſ-s ligature. Still, we encode both variants as > identical letters. I’ve got a print from 1739 with legends in both > German (blackletter) and French (Roman italics), comprising both types > of ligatures in one single document. There's another, lesser German analogy. If I understand correctly, in some styles the diaeresis and umlaut marks may be distinguished visually. While it is permissible to use CGJ to mark the difference, the TUS claims (TUS 9.0 p833, in Section 23.2) that CGJ does not affect rendering, except for the direct effect of blocking canonical reordering. (This does appear to be in contrast to its seemingly archaic effect in inhibiting line-breaking.) However, combining marks are, by policy, unified more readily than letters. Richard.