"Upgrading" is not an option

[J S]

I recently started a thread here about syntax highlighting and mentioned that I am using VIM 7.4 Someone "helpfully" suggested "upgrading" my VIM version.

Anyway, upgrading is not an option. Please do not mention this again. Thank you.

[Tim Chase]

You asked for help but omitted the detail. Someone, in a effort to
help troubleshoot asked if upgrading your nearly-decade-old install
was an option. And you replied brusquely without further explanation.

Please curb the rudeness in response to efforts to help.

You haven't detailed the platform on which you're running vim (Linux?
a BSD? MacOS? Windows? DOS?).

Upgraded versions come with updates syntax scripts that might address
your issue, so it was a perfectly reasonable inquiry.

Vim can be downloaded, compiled, and run entirely from your $HOME
directory if needed with no need to touch the system version of Vim.
So it's perfectly reasonable to consider this "upgrade" option, even
if it's not on a machine you administer.

Unless perhaps support for your OS was dropped (reading `:help
os_msdos.txt` on a contemporary version says that 7.4 was the last
release built for MSDOS). If this is the case, that's valuable
information to those trying to help. I mean, you're asking to write
shell-scripts which are Unix-like, but I suppose it's possible you're
authoring them on DOS and then transporting them to a unixlike
machine.

Alternatively, it might be possible to drop the related 8.x syntax
files into your 7.4 install (or at a strategic location in your $HOME
as a user if you lack sysadmin access) and get improved syntax
highlighting without fully upgrading the vim install itself.
However, newer versions of vim support newer syntax features, so you
might have to modify the syntax files to remove functionality added
since 7.4. As best I can tell, at least "syn-include" was available
in 7.3 so you should be able to at least get some syntax inclusion.

Finally, the help documents are thorough, so if you can target the
invocations such as `expect -c '{stuff}'`, you might be able to
formulate your own syntax-include region, even if it's not readily
provided by existing syntax files.

-tim