mnotes package error: Incomplete \iffalse

Question

I'm trying to use the mnotes package (\usepackage{mnotes}), which is a package for adding comments to the margins that point to text in the document.

but I'm getting this error:

(C:\ProgramsPortable\miktex-portable\texmfs\install\tex/latex/mnotes\mnotes.sty
)
! Incomplete \iffalse; all text was ignored after line 70.
<inserted text>
                \fi

I tried looking at the code in mnotes.sty, but I couldn't see any mismatched \ifs or \fis (as far I can see, though I'm no latex expert).

Turning on "basic" mode allows it to run, but functionality is greatly reduced:

\usepackage[basic]{mnotes}

Any ideas why this error is happening? Is the problem within mnotes or perhaps a dependency?

Answer 1

I made a MWE to test this issue, and the problem went away! I started adding in lines one-by-one from my original tex file until the issue re-appeared.

MWE with no issues:

\documentclass[dvipsnames]{article}
\usepackage{mnotes}
\begin{document}
Hello world \MNOTE{This is an mnote} Goodbye
\end{document}

Once I added the line which imports algorithm2e (for pseudocode formatting), then it broke again. But moving the mnotes import to be before algorithm2e fixes the problem (Note: I didn't test whether the pseudocode still works), like so:

\usepackage{mnotes}
\usepackage[linesnumbered,vlined,figure,tworuled]{algorithm2e}

However, back in my original document, I moved the mnotes import to be the first line after \documentclass and my problem still occurrs.

Next I removed ALL the \usepackage lines in my original document and started adding them back in. It broke once I got to \usepackage{ulem}. Even though that package comes after \usepackage{mnotes}, it still conflicts.

Conclusion: mnotes conflicts with other packages, if getting an error, remove other \usepackage lines until it works.