redneb questions

redneb answers

• GROUP BY PostgreSQL query where I need a column that is not in the GROUP BY clause [duplicate]
• postgres sql , how to increment when null exists
• perl magic symbols -w -r and _
• make function round up to nearest quarter hour
• Regex - Match string that with : and space
• Functor instance for (newtype Mu f = InF {outF :: f (Mu f)})
• Javascript/CSS - animation duration in pixel per second
• What is the purpose of the extra result parameter of atomicModifyIORef?
• How to capture all output of a command which also requires user input from terminal?
• Passing struct-like data between C and Haskell via the FFI