Haskell doesn't really have the problems that are commonly associated with operator overloading.

Haskell does have type classes, which do allow overloading, even of operators, but the type class uniquely determines the type of the operator - and there can be only one definition of any operator in scope.

Also, you can just define as many new operators as you like.

For these reasons, you can't have the madness of operator<< in C++, or whatever it is that Perl does with the same operator doing 5 completely different things depending on context.