Am Thu, 16 Nov 2017 10:28:56 +0100 schrieb Hans Hagen: >> Can one query the number by name? So that >> \Umiddle class \directlua{whatever(rel)} gives now 5 and in the >> next version 3?
> these numbers are documented part of traditional tex, so we use that > 'rel' number now (the internal ones are just that: internal) My question was how to write code that works in a current texlive (where you need \Umiddle class 5 to get relation spacing) *and* in a future luatex where class 3 will be the correct value. Is querying the luatex version the only way? -- Ulrike Fischer http://www.troubleshooting-tex.de/