If Haskal is that good then...

...then why does GHC requires Perl 5? The answer is here¹:

I ​noticed that this adds 30.000 lines of C and 1700 lines of Haskell. Not sure if that's any better than just bundling Perl on Windows + a 300 line Perl script.

_________________

^{[1] - https://ghc.haskell.org/trac/ghc/ticket/9832#comment:12}

>>8
Any person who is smart enough to understand non-FIOC languages should be able to understand Perl code just fine. But here is a question for you: how much time a given person would need to understand what's behind IO operations in Haskell? I can't give you an exact estimation but I can tell you one thing, a person can memorize the complete perldoc (including the regex engine and all core modules) before that happens.