On 19-2-2012 07:25, Paul Isambert wrote:
luatex hyphenates the whole list in one go and does not do this delayed and partial as in traditional tex ... this is on purpose as it provides callback code with the whole lot (in luatex the hyphenation / ligature building and justification steps are separated) ... also, there is no reason not to hyphenate the first word if you have real narrow columns.
I agree, it's just that TeX3 does otherwise.
btw, similar differences in engines can be found in ligature de/re composition where tex3 does some juggling that luatex doesn't (for good reason)
The parameters are obeyed in all other engines, exception or not; I suppose the reason is that they may very well change in the course of the document.
Ok, but as luatex can have more advanced content in \hyphenation it is more tricky (and probably costly) to have dynamic adaption to those min values so I wonder if it's worth the trouble.
But actually I've just found things are a little bit more complicated: LuaTeX doesn't hyphenate a word if it is shorter than \lefthyphenmin + \righthyphenmin (which makes sense); but if the word is hyphenated, and it is an exception, then it gets hyphens everywhere, whatever the values of the parameters:
ok, that's weird indeed and could qualify as a bug Hans ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | voip: 087 875 68 74 | www.pragma-ade.com | www.pragma-pod.nl -----------------------------------------------------------------