Using \ExplSyntaxOn breaks \xpatchbibmacro. Can this be fixed, or will I just need to use xpatch commands elsewhere?
MWE:
\documentclass{article} \usepackage{expl3} \usepackage{xpatch} \usepackage[style=authoryear]{biblatex} \begin{filecontents}[overwrite]{\jobname.bib} @book{1person, author = {John Smith}, title = {Some Random Thing}, date = {1970} } @book{2people, author = {John Smith and Bob Smith}, title = {Some Other Thing}, date = {1971} } \end{filecontents} \addbibresource{\jobname.bib} \nocite{*} \DeclareNameAlias{sortname}{given-family} \ExplSyntaxOn % Removing this fixes it... \xpatchbibmacro{date+extradate}% Remove date's parentheses, add period before (/a/428193) {\printtext[parens]}{\setunit*{\addperiod\addspace}\printtext}{}{} \ExplSyntaxOff \begin{document} \printbibliography \end{document} 
\ExplSyntaxOn?l3keys, and there's a lot of conditional groups.\ExplSyntaxOncan't be put into groups, which forces me to split and double my conditionals.expl3syntax changes quite a few of them, so patching breaks. For example, if a command contains a~and then you patch it, it becomes a space inexpl3syntax.