Perl 6 is a completely new language, but that doesn't mean it's incompatible. Inline::Perl5 provides a rather extensive compatibility layer with Perl 5: https://github.com/niner/Inline-Perl5

By this logic, Perl is also compatible with the many other languages for which there are Inline:: modules.

The Perl 6 Inline::Perl5 automatically maps Perl 5's syntax, object system semantics, exceptions, etc. to Perl 6's so that Perl 6 users don't in principle have to know about Perl 5, just the logical API of any used module/library/function.

I don't think the Perl 5 inlines do this.