Thus, what happens today? People ask Haskell-Cafe how to implement global
variables and they are advised to use IORefs and unsafePerformIO, although
the better answer is: "Why do you want to do this?" Even "Tackling the
awkward squad" considers unsafePerformIO an acceptable tool for handling
global configuration files.

One problem here is that the Haskell-style alternatives to global parameters aren't as convenient as to use.

We should consider stealing Agda's module system for Haskell 2.0.