I've heard a rumour that POSIX mandates that Perl be installed, although I haven't been able to substantiate it.
POSIX-described Turing-complete interpreters include at leat the Bourne shell, awk, and sed, none of which you probably want to use for implementing a security policy.
Apparently LSB 5.0 mandates[1] both Perl (5.8) and Python (2.4), but that won't pacify anyone with an axe to grind about applications making Linux-specific assumptions.
> Apparently LSB 5.0 mandates[1] both Perl (5.8) and Python (2.4)
Wow, that didn't age well. That document actually says Python "2.4.2 or greater" and Perl "5.8.8 or greater", which doesn't help if the installed interpreters are Python 3.10 and Perl 6.c (2018.06), since both are greater than the specified versions but incompatible with them. Even if it had specified the major release (that is, Python 2.x greater than 2.4.2 and Perl 5.x greater than 5.8.8), that wouldn't help once those major releases are no longer maintained.
Python3 requires some code changes, but on the whole is the same language.
Perl 6 was intended to be an upgrade from 5, but over time developed into a completely new language that shared stylistic similarities to Perl 5. Perl 6 can't be compatible with Perl 5 to any large extent because XS isn't a thing anymore, so any modules that had binary parts to them can't be easily ported.
These days Perl 6 got renamed to "Raku", to signify that it's its own, independent language.
The Perl 5 line continues to exist and apparently plans for the next major version to be Perl 7.
POSIX-described Turing-complete interpreters include at leat the Bourne shell, awk, and sed, none of which you probably want to use for implementing a security policy.
Apparently LSB 5.0 mandates[1] both Perl (5.8) and Python (2.4), but that won't pacify anyone with an axe to grind about applications making Linux-specific assumptions.
[1]: https://refspecs.linuxfoundation.org/LSB_5.0.0/LSB-Languages...