Option to hide text while maintaining synctex.gz functionality

Question

My goal is the following: I would like to write exercises and their solutions in a single tex file with the option of hiding the solution, so that I do not need two separate tex files for the question file and the sample solution. In the tex file, I want to have something like

\documentclass{article}
\def\generateSolution{1} % 0 or 1
\usepackage{my_stylefile}
\begin{document}
... question ...
\solution{
...
}
\end{document}

Here, \solution is defined in my_stylefile and the solution is either shown or hidden depending on the value in \generateSolution (which gets accessed by the stylefile).

What is important to me is the functionality of the synctex.gz file, which enables some LaTeX editors to jump to the correct line in the pdf by clicking on the line in the tex file and vice versa. I have found ways to hide text, but none that preserve this functionality and can be moved to the stylefile.

The problem is that the synctex.gz file only recognizes the beginning and end of the block \solution{...}. I do not know a way around this.

Thus, it seems like the better approach to have something of the form

\begin{solution}
...
\end{solution}

Here, the comment package would come in handy. However, when I try somehting like the following in the stylefile

\usepackage{comment}
\if\generateSolution0
\newenvironment{solution}{\begin{comment}}{\end{comment}}
\else
\newenvironment{solution}{}{}
\fi

then I run into this error.

The best solution I have thus far is the following: stylefile:

\newcommand{\BeginSol}{\if\generateSolution1
{\large\textbf{\Solution:}}}

and tex file:

\BeginSol
solution text
\fi

However, this is not quite satisfactory as I cannot move the "\fi" in the stylefile as it has to appear explicitly in the tex file. Moreover, if I want to add cosmetical features, e.g. put the solution in an mdframed environment, then the "\end{mdframed}" will also appear in the tex file:

\newcommand{\BeginSol}{\if\generateSolution1
{\large\textbf{\Solution:}}\begin{mdframed}}

\BeginSol
solution text
\end{mdframed}\fi

Any suggestion is welcome! Cheers.

PS: As this is my first post on tex.stackexchange, I am not familiar with the appropriate tags.

Answer 1

\excludecomment{solution} from the comment package does the trick:

\documentclass[]{article}
\def\generateSolution{1}
\usepackage{comment}
\if\generateSolution1
\newenvironment{solution}{\textbf{Solution:}}{}
\else
\excludecomment{solution}
\fi
\begin{document}
Always show this
\begin{solution}
I only want these paragraphs in the case showSolution is set to 1
BB
CC
DD
EE
FF
GG
HH
II
JJ
KK
LL
MM
NN
\end{solution}
\end{document}

The above solution works well for me in Overleaf. Double clicking a paragraph in the pdf preview of Overleaf makes the cursor jump to the correct paragraph in the TeX source code.

As far as I understood the documentation of comment the following alternative version should work as well, but in practice synctex.gz does not work for me in Overleaf for the following version:

\documentclass[]{article}
\def\generateSolution{1}
\usepackage{comment}
\if\generateSolution1
\includecomment{solution}
\else
\excludecomment{solution}
\fi
\begin{document}
Always show this
\begin{solution}
I only want these paragraphs in the case showSolution ist set to 1
BB
CC
DD
...
\end{solution}
\end{document}

I don't really understand why the second version does not work, but luckily the first version works well, so there is no need to use the second version.

These solutions are inspired from the answers https://tex.stackexchange.com/a/3025/128042, https://tex.stackexchange.com/a/3026/128042 and https://tex.stackexchange.com/a/3073/128042 to the question Latex tag for making a comment appear or disappear in pdf?.