Cfrgtkky

I am encountering an odd problem. I want to create composite characters such as ǎ using the newunicodechar package. However, it only yields a result in combination with the xeCJK package.

This code produces missing characters:

documentclass[a4paper,12pt,article,oneside]{memoir}

usepackage{fontspec}

usepackage{xunicode}



usepackage[british]{babel}



setmainfont[Ligatures=TeX]{Minion Pro}



usepackage{newunicodechar}

newunicodechar{ǚ}{v{ü}}

newunicodechar{Ǚ}{v{Ü}}

newunicodechar{ǎ}{v{a}}

newunicodechar{Ǎ}{v{A}}

newunicodechar{ǒ}{v{o}}

newunicodechar{Ǒ}{v{O}}





begin{document}



ǚ Ǚ ǎ





end{document}

If I load the xeCJK package then the characters render just fine.
Why is that? And how to generate composite characters without the named package?

Note:

• this is reproducible with other fonts that do not contain the unicode characters (e.g. Adobe Garamond Pro)


• Minion Pro does contain a caron character (unicode 02C7, index 136)

The default setup doesn't use unicode U+02C7, but the combining accent U+030C which is missing in your font. xecjk contains some code to use U+02C7 instead, but seems to use this code only if xunicode is loaded too - which is a bit of a pain, as normally one shouldn't use it anymore.

You can clone the xeCJK code by using add@accent. If more fonts are involved where some have the combining accent, some additional checks for glyph existence are probably needed.

documentclass[a4paper,12pt,article,oneside]{memoir}



usepackage{fontspec}

usepackage[british]{babel}



setmainfont[Ligatures=TeX]{MinionPro-Regular.otf}



usepackage{newunicodechar}

makeatletter



newunicodechar{ǚ}{add@accent{`^^^^02c7}{ü}}

newunicodechar{Ǚ}{add@accent{`^^^^02c7}{Ü}}

newunicodechar{ǎ}{add@accent{`^^^^02c7}{a}}

makeatother

%newunicodechar{Ǎ}{v{A}}

%newunicodechar{ǒ}{v{o}}

%newunicodechar{Ǒ}{v{O}}

%

begin{document}

abc 



ǚ Ǚ ǎ



end{document}

Based on a trick by Egreg, this uses the accent primitive. I chose to simply redefine v.

documentclass{standalone}

usepackage{fontspec, newunicodechar}



usepackage[british]{babel}



setmainfont[Ligatures=TeX]{Cardo}



renewcommandv[1]{accentstring"02C7 #1}



newunicodechar{ǚ}{v{ü}}

newunicodechar{Ǚ}{v{Ü}}

newunicodechar{ǎ}{v{a}}

newunicodechar{Ǎ}{v{A}}

newunicodechar{ǒ}{v{o}}

newunicodechar{Ǒ}{v{O}}



begin{document}



ǚ Ǚ ǎ Ǎ ǒ Ǒ



end{document}

I picked Cardo as a common font that contains the caron accent, but not the precomposed ǚ.