In complex files, especially when writing packages with basic TeX-LaTeX code, the standard definition of foldmarker, namely {{{,}}}, is unfortunate — in effect is quite common to have pieces of code like:

\pgfkeys{/tikz/t/.add code={}{\ctikzset{text=#1}}}

which will trigger the fold closing mechanism. What I am doing is adding on the top of my files the following:

% vim: set fdm=marker fmr=%<<<,%>>>:

because I think that this will make the folders independent of the settings of other contributors.

Is this a sensible way of doing folding with TeX? Is there any commonly used setting of foldmarker for TeX/LaTeX I should be aware of, and use it instead of inventing my own?

1 Answer 1


You might want to consider adopting the vimtex plug-in, which improves support for TeX files in Vim.

Among its features, it supports custom folding, which is able to recognize LaTeX blocks delimited with \begin{...} and \end{...} and use them to define folding.

Furthermore, it recognizes {{{ and }}} but only within comments.

See vimtex's documentation under :help vimtex-folding for more details, in particular :help g:vimtex_fold_types which allows you to customize it.

If you decide to use foldmethod=marker with the custom <<< and >>> markers, then instead of fmr=%<<<,%>>>, consider using:


Without the leading % comment character.

You're of course going to use those inside comments, so in practice you'll end up using %<<< often. However, matching only <<< as the marker has advantages, since then you could use additional text at the start of the comment, for example describing the block:

% Introduction <<<

And the other advantage is that you can precede the marker with a level number, in which case you can for the most part skip the closing markers, if you use matching levels on them:

% Introduction 1<<<
% Chapter 1: Motivation 1<<<

The choice of <<< and >>> is such that this sequence is very unlikely to happen in the normal body of the text, so forcing them to appear at the start of the comment, with %<<<, isn't totally necessary.

(Though note that using %<<< still allows using them this way, for example you could have %<<< or even 1%<<< inside a comment.)

  • Yes, I use vimtex --- the automatic folding is great for LaTeX files, but for low-level TeX files like the ones in the circuitikz core (the package I maintain) automatic folding is at best not useful, and it is quite slow.
    – Rmano
    Commented Jun 28, 2020 at 17:16
  • 1
    Note that vimtex can handle {{{ and }}} within comments, so using %{{{ etc. might be helpful. See also the reference to g:vimtex_fold_types which allow you to customize automatic folding. Having said that, perhaps fdm=marker works best for you, so since you can easily set that up from a modeline, maybe that's the best choice for you!
    – filbranden
    Commented Jun 28, 2020 at 17:21
  • 1
    I've read the vimtex_fold_types and especially the markers option, and hat would be great, matching the pattern only inside comments solves my problem. But problem is that a collaborator that does not use vimtex will have the folding completely wrong. So yes, this is the solution, even if I can't use it on some file...
    – Rmano
    Commented Jun 28, 2020 at 17:38
  • 1
    @Rmano Updated the answer with a further recommendation on using foldmarkers inside comments.
    – filbranden
    Commented Jun 28, 2020 at 18:44
  • I think that the syntax for the level number is after the marker, like %>>>1...
    – Rmano
    Commented Jun 29, 2020 at 8:55

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.