The Enum instances for Float and Double have dubious semantics which cause endless confusion, e.g. http://stackoverflow.com/questions/13203471/the-math-behind-1-09999999999999..., http://stackoverflow.com/questions/9810002/floating-point-list-generator, http://stackoverflow.com/questions/7290438/haskell-ranges-and-floats, http://stackoverflow.com/questions/10328435/how-to-solve-floating-point-numb..., and many more. I would therefore like to propose that the usage of an Enum instance of Float or Double generate a compiler warning, such as "The Enum instance of Float is subject to rounding errors". Deadline: 2 weeks. Pedantic question: Should it be the Enum instance _of_ Float or _for_ Float? -- View this message in context: http://haskell.1045720.n5.nabble.com/Proposal-Warn-when-using-Enum-instance-... Sent from the Haskell - Libraries mailing list archive at Nabble.com.