How do I sanitize LaTeX input?

Question

I'd like to take user input (sometimes this will be large paragraphs) and generate a LaTeX document. I'm considering a couple of simple regular expressions that replaces all instances of "\" with "\textbackslash " and all instances of "{" or "}" with "\}" or "\{".

I doubt this is sufficient. What else do I need to do? Note: In case there is a special library made for this, I'm using python.

Update: To clarify, I do not wish that anything be parsed treated as LaTeX syntax. $a$ should be replaced with \$ a\$.

Answer 1

If your input is plain text and you are in a normal catcode regime, you must do the following substitutions:

• \ → \textbackslash{} (note the empty group!)
• { → \{
• } → \}
• $ → \$
• & → \&
• # → \#
• ^ → \textasciicircum{} (requires the †extcomp package)
• _ → \_
• ~ → \textasciitilde{}
• % → \%

In addition, the following substitutions are useful at least when using the OT1 encoding (and harmless in any case):

• < → \textless{}
• > → \textgreater{}
• | → \textbar{}

And these three disable the curly quotes:

• " → \textquotedbl{}
• ' → \textquotesingle{}
• ` → \textasciigrave{}