\documentclass{article}
\usepackage{mykeyval}
\begin{document}
Simple KV no options: \KVsimple
Simple KV with options: \KVsimple[width=100, height=200]
Complex KV no options: \KVcomplex
Complex KV with options: \KVcomplex[width=100, height=200]
Filenames \KVsimple[path=a_dir/~foo.bar]
Filenames \textbf{\KVsimple[path=a_dir/~foo.bar]}
KV Environment no options:
\begin{KVenv}
Inside the environment.
\end{KVenv}
After the environment.
KV Environment with options:
\begin{KVenv}[width=100, height=200]
Inside the environment.
\end{KVenv}
After the environment.
KV Environment with structure no options:
\begin{KVstruct}
Inside the environment.
\end{KVstruct}
After the environment.
KV Environment with structure with options:
\begin{KVstruct}[width=100, height=200]
Inside the environment.
\end{KVstruct}
After the environment.
KV automatic conversion to structure
\KVauto{width=100, height=200}
\end{document}