Does stringi export something like `u_hasBinaryProperty(c, UCHAR_ALPHABETIC)`?

I am writing a parser for LaTeX code, and I'm hoping to support UTF-8 input. TeX and LaTeX categorize each input character, and one of the categories is whether it is a letter or not. I'm not sure how the Unicode-supporting versions of LaTeX handle this, but one thing I wanted to try was to use the ICU test `u_hasBinaryProperty(c, UCHAR_ALPHABETIC)`. That's the only ICU function I need, so linking ICU into my package is possible but seems like overkill.

Does stringi provide this kind of categorization of the characters in a string? Ideally it would be something I could call from C, but if it's only available from R that would be very helpful too. I couldn't spot it in the reference docs, but maybe I just missed it.