XeTeX/LuaTeX and inputenc package.

[Hongyi Zhao]

Hi here,

According to the documentation and specifications of certain TeX
engines (such as XeTeX and LuaTeX), they may not use the inputenc
package to process Unicode characters, and instead use different
methods to handle them. In these engines, the
`\DeclareUnicodeCharacter` command may be ignored because they use
different Unicode mappings. If similar issues are encountered when
using these engines, which alternative commands or solutions may need
to be used to handle Unicode characters properly, say, for the
following one?

\usepackage[utf8]{inputenc}
%solve unicode error
\DeclareUnicodeCharacter{2212}{\textendash}

See here [1] for the related discussion.

[1] 
https://tex.stackexchange.com/questions/517845/declareunicodecharacter-undefined-control-sequence

Regards,
Zhao
-- 
Assoc. Prof. Hongsheng Zhao <hongyi.zhao@gmail.com>
Theory and Simulation of Materials
Hebei Vocational University of Technology and Engineering
No. 473, Quannan West Street, Xindu District, Xingtai, Hebei province