Variations in ldots

Here is my code:

 \documentclass{article}
%\usepackage{unicode-math}
%\setmathfont{Latin Modern Math}
\begin{document}
The letters $a, \ldots, z$ are used.
\end{document}


It produces this output, when typesetting with XeLatex:

If I uncomment the second line, I get:

If I uncomment the second and third lines, I get:

My questions are:

(1) Are these the expected/correct results, or does it look like my TeX or font installation is somehow messed up?

(2) I suppose the third result is a consequence of the design of the ellipsis character in the Latin Modern fonts. Is this design as intended, or is it regarded as a bug? I personally don't like how it looks, but that's just a matter of taste, I guess.

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In my opinion this is not the expected/correct result; one may find the usual dots too spaced out, but at least there should be the possibility to choose from different dot spacing. However, I get the same result whether or not Latin Modern Math is loaded. – egreg Jun 23 '13 at 9:16
> I get the same result whether or not Latin Modern Math is loaded. So, in other words, you get the same result for my cases #2 and #3? So, that means there is something wrong with my configuration. Or, it's different from yours, anyway. – bubba Jun 23 '13 at 11:18

unicode-math changes \mathellipsis to mean

\mathinner{\unicodeellipsis}


where \unicodeellipsis just prints the character … in whatever is the current font (Latin Modern Math, if you don't set another one).

This does make sense, because, for instance, one can then copy-paste the dots and get a single character rather than three periods.

However I don't like at all this kind of Unicode police that forces a using glyphs based on the preferences of whoever created the font. Right or wrong, spaced out dots are used and the authors of Latin Modern Math should acknowledge it. Adding a stylistic variant to an OpenType font is not difficult.

If you want to revert to the spaced out dots (but using three periods), add

\AtBeginDocument{%
\renewcommand\mathellipsis{\mathinner{\ldotp\ldotp\ldotp}}%
}


after loading unicode-math.

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Sounds like Unicode should have a "math-ellipsis" character, maybe, with wider spacing. I don't expect that will happen anytime soon. But defining my own mathellipsis command isn't too bad, and I can space the dots however I like. I guess that's what I'll do. – bubba Jun 23 '13 at 11:16
The authors of Latin Modern were just following the Unicode standard, I suppose. That's why they didn't create a widely-spaced ellipsis glyph. – bubba Jun 23 '13 at 11:20