In real life, I find that Haskell suffers from trying too hard to use the most general concept that‘s applicable (no pun intended). Haskell programs happily use “Either Err Val” and “Left x” where other languages would use the more expressive but less general “Result Err Val” and “Error x”. Also, I don’t want to mentally parse nested liftM2s or learn the 5th effect system ;-)

Ever seen a ROM?

And the C library‘s hacks around not being able to overload functions (which is the only reason for strstr et al‘s weird signature) wouldn‘t stop me from using const. It can be really useful both for documentation and for correctness. Think memcpy, not strstr.

   auto askForUsername = [&] { … };
   auto lookupUserByName = [&](auto name) { … };
   auto printUserDetails = [&](auto userId) { … };
   
   auto details = 
     askForUsername()
       .and_then(lookupUserByName)
       .and_then(printUserDetails);