I'm trying to use beamer's renewcommand, and for understanding this I just tried to copy the example in the "9.6.1 Making Commands and Environments Overlay Specification-Aware" section:
\renewenvironment<>{verse}
{\begin{actionenv}#1\begin{originalverse}}
{\end{originalverse}\end{actionenv}}
! LaTeX Error: Command \beamerx@\verse already defined.
Or name \end... illegal, see p.192 of the manual.
See the LaTeX manual or LaTeX Companion for explanation.
Type H <return> for immediate help.
...
l.5 {\end{originalverse}\end{actionenv}}
Am I doing something stupid? I am just copying the example. Beamer version is 3.36 and latex is
This is pdfTeX, Version 3.14159265-2.6-1.40.16 (TeX Live 2015) (preloaded format=pdflatex)
Thanks,
Albert