If you are anal about getting every edge case correct, Unicode is a straight up nightmare to support.

Even in Perl's supposedly superior support has issues. See how deep the rabbit hole goes by reading the first response to the question here:

https://stackoverflow.com/questions/6162484/why-does-modern-...

There is really no way for a simple program to account for all of those possible edge cases. Something as simple as a print of a string can be a minefield depending on what is in those characters. And it's not like the old days where you could safely filter out all non-printable characters to avoid most problems. Have you considered how your formatting is going to look when people intersperse Right to Left words in your output for example?