How to format custom .cwl for TeXstudio completion

Question

I am creating my own custom .cwl file for TeXstudio. What command should I put in my .cwl file to get the following completion:

\begin{lemma}
    content...
\end{lemma}

with content... specified as a placeholder?

Answer 1

The .cwl file should look like:

\begin{lemma}%\    %<content...%>%\\end{lemma}

and should be saved in C:\Users\[UserName]\AppData\Roaming\texstudio\completion\user for Windows or /.config/texstudio/completion/user on Linus/macOS. Then go into Options -> Configure TeXstudio -> Completion and tick the box next to your .cwl file name.