In the file /etc/nanorc there is following line:
## To include all existing syntax definitions, you can do:
include "/usr/share/nano/*.nanorc"
Here is the content of /usr/share/nano/:
debian@beaglebone:~$ ls /usr/share/nano/ -l
total 180
-rw-r--r-- 1 root root 882 Jun 12 2019 asm.nanorc
-rw-r--r-- 1 root root 555 Jun 12 2019 autoconf.nanorc
-rw-r--r-- 1 root root 1342 Jun 12 2019 awk.nanorc
-rw-r--r-- 1 root root 712 Jun 12 2019 changelog.nanorc
-rw-r--r-- 1 root root 788 Jun 12 2019 cmake.nanorc
-rw-r--r-- 1 root root 1748 Jun 12 2019 c.nanorc
-rw-r--r-- 1 root root 344 Jun 12 2019 css.nanorc
-rw-r--r-- 1 root root 757 Jun 12 2019 debian.nanorc
-rw-r--r-- 1 root root 414 Jun 12 2019 default.nanorc
-rw-r--r-- 1 root root 1108 Jun 12 2019 elisp.nanorc
-rw-r--r-- 1 root root 1967 Jun 12 2019 fortran.nanorc
-rw-r--r-- 1 root root 4226 Jun 12 2019 gentoo.nanorc
-rw-r--r-- 1 root root 1317 Jun 12 2019 go.nanorc
-rw-r--r-- 1 root root 710 Jun 12 2019 groff.nanorc
-rw-r--r-- 1 root root 587 Jun 12 2019 guile.nanorc
-rw-r--r-- 1 root root 1211 Jun 12 2019 html.nanorc
-rw-r--r-- 1 root root 653 Jun 12 2019 java.nanorc
-rw-r--r-- 1 root root 763 Jun 12 2019 javascript.nanorc
-rw-r--r-- 1 root root 878 Jun 12 2019 json.nanorc
-rw-r--r-- 1 root root 2459 Jun 12 2019 lua.nanorc
-rw-r--r-- 1 root root 535 Jun 12 2019 makefile.nanorc
-rw-r--r-- 1 root root 453 Jun 12 2019 man.nanorc
-rw-r--r-- 1 root root 198 Jun 12 2019 mgp.nanorc
-rw-r--r-- 1 root root 185 Jun 12 2019 mutt.nanorc
-rw-r--r-- 1 root root 388 Jun 12 2019 nanohelp.nanorc
-rw-r--r-- 1 root root 2675 Jun 12 2019 nanorc.nanorc
-rw-r--r-- 1 root root 791 Jun 12 2019 nftables.nanorc
-rw-r--r-- 1 root root 1696 Jun 12 2019 objc.nanorc
-rw-r--r-- 1 root root 859 Jun 12 2019 ocaml.nanorc
-rw-r--r-- 1 root root 590 Jun 12 2019 patch.nanorc
-rw-r--r-- 1 root root 1457 Jun 12 2019 perl.nanorc
-rw-r--r-- 1 root root 1070 Jun 12 2019 php.nanorc
-rw-r--r-- 1 root root 919 Jun 12 2019 po.nanorc
-rw-r--r-- 1 root root 3046 Jun 12 2019 postgresql.nanorc
-rw-r--r-- 1 root root 632 Jun 12 2019 pov.nanorc
-rw-r--r-- 1 root root 1199 Jun 12 2019 python.nanorc
-rw-r--r-- 1 root root 1506 Jun 12 2019 ruby.nanorc
-rw-r--r-- 1 root root 1116 Jun 12 2019 rust.nanorc
-rw-r--r-- 1 root root 1489 Jun 12 2019 sh.nanorc
-rw-r--r-- 1 root root 1924 Jun 12 2019 spec.nanorc
-rw-r--r-- 1 root root 2181 Jun 12 2019 tcl.nanorc
-rw-r--r-- 1 root root 463 Jun 12 2019 texinfo.nanorc
-rw-r--r-- 1 root root 200 Jun 12 2019 tex.nanorc
-rw-r--r-- 1 root root 527 Jun 12 2019 xml.nanorc
debian@beaglebone:~$
But there is no syntax coloring for any of languages.
Where is the problem ?
Thanks