This directory mainly contains improved and completely new JOE syntax files fixing bugs in the original files and adding support for new languages.
To enable the .jsf files in this repository they need to appear in JOEs syntax directory. This is likely to be /usr/share/joe/syntax when using Debian and APT or /usr/local/Cellar/joe/3.7/share/joe/syntax when using brew on Mac OS X. You may download the latest jsf-bundle and place it's contents into the syntax directory (Note: this bundle might be outdated compared to the repository's state).
A maybe better way to achieve this is to clone this repository somewhere onto your hard disk and establish symlinks to all jsf files in the syntax directory.
To enable the enhanced ftyperc from this repository to gain syntax highlighting support for new languages without overwriting /etc/joe/ftyperc, you may place the modified one in ~/.joe/ as ~/.joe/ftyperc.
See HowItWorks.md which is a reworked version of the header of c.jsf. Another good resource might be jsf.jsf.
For JOE see here.
For JOE project see here.
For original JOE syntax files see here.
You can find this repository here.