Hello, I've been trying to work out if the current expl3 has anything like \patchcmd from etoolbox. Will suggested looking at the various \tlp_ ... macros. However, even a simple two-part test in this way fails: \documentclass{article} \usepackage{expl3} \CodeStart \cs_if_really_exist:cT{thanks}{ \tlp_if_in:NnT\thanks{\footnotemark}{ % Do something } \tlp_if_in:NnT\thanks{\footnotetext}{ % Also do something } } \CodeStop \begin{document} \end{document} I guess I'm abusing the functions. So have I missed something obvious? The ability to patch existing functions is very handy. -- Joseph Wright