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

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.