Compilation error when string testing using csvsimple

Question

Consider this minimal working example:

    \documentclass{beamer}
    \usepackage{csvsimple,filecontents}

    \begin{document}

    \begin{filecontents*}{data.csv}
    id,type
    1,a
    2,b
    \end{filecontents*}

    \begin{frame}    
    \csvreader{data.csv}{1=\id,2=\type}{
        \ifcsvstrcmp{\type}{a}{
        %do something
        }{
        %do something else
        }       
    }
    \end{frame}

    \end{document}

The above code does not compile unless the \ifcsvstrcmp{}{}{}{} is commented out.

Here's the error message:

pdflatex> ! Undefined control sequence.
pdflatex> \csv@@body -> \ifcsvstrcmp
pdflatex> --------------------------------------{\type }{a}{}{}
pdflatex> l.14 }

Appreciating any hints on what I might be doing wrong here...

Thx!

Answer 1

Debugging can be difficult. Often, the problem isn't a bug, but the user misunderstanding the macro's syntax or limitations. Often, it is just a simple typo on your input, misspelling a macro name or mismatching your braces. As KJO noted, a really annoying problem is when non-printing characters slip into your input. These can be maddening to find and eliminate.

When all those avenues come up dry, another avenue to check is whether your packages are out of date or mismatched with each other. This is what I suggested to the OP by way of comment.

Upon updating all of his packages, the problem went away, therefore confirming that an outdated package was the source of the issue.