Mixing two syntax highlighting scripts

Question

I write blog posts with Jekyll, and for that I end up using three different languages in the same file: YAML at the start for post metadata, Markdown in the body, and C++ in

Answer 1

Quick fix: append syntax on to the last line of your .vimrc, which is the same as setting :syn on in the live session.

Not So Quick:

Looks like you might have installed the custom 'jekyll' syntax alongside the default syntax files in $VIMRUNTIME.

According to Vim wiki section on custom syntax, it's preferable to keep all personal customizations within ~/.vim. For example, putting your jekyll.vim syntax in ~/.vim/syntax/.

Do not use a directory containing the files distributed with Vim because that will be overwritten during an upgrade (in particular, do not use the $VIMRUNTIME directory).

In the Vim syntax docs:
:syntax enable runs ':source $VIMRUNTIME/syntax/DEFAULT_SYNTAX.vim'.
:syn on (or :syntax on) will "overrule your settings with the defaults".

So if setting :syntax on makes your custom syntax work, it must be contained in the default syntax set.

Try keeping all the custom stuff in ~/.vim and see if that settles things.