On 25-10-2012 14:12, luigi scarso wrote:

$\overrightarrow{ab}$ $\underrightarrow{ab}$

both give the same result ($\underrightarrow{ab}$)

a few under/over mixups in math-arr.mkiv: line 429 and 434 Question for Aditya: We have this arrow module, but as luatex has better under / over fill support, we could use: % \unexpanded\def\underrightarrow#1{\mathop{\Uunderdelimiter \defaultmathfamily "2192 {#1}}} % \unexpanded\def\overrightarrow #1{\mathop{\Uoverdelimiter \defaultmathfamily "2192 {#1}}} which actually gives a different spacing. So the question is: how valid is the arrow module? btw, The old kludges wrt left/right arrow fills with text above as used in chemical reactions is solved using virtual characters ... I discussed this with Gyre Math Font Gurus and we agreed that it makes sense to have such double arrow combination snippets in the fonts ... it was also discussed that we should have a well defined private space in unicode for additional characters) 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 -----------------------------------------------------------------