To be fair, the book isn't complete yet and it hasn't nearly reached 1.0 yet. Some other listed languages are at similar stages of development, like Nim, Crysta

To be fair, the book isn't complete yet and it hasn't nearly reached 1.0 yet. Some other listed languages are at similar stages of development, like Nim, Crystal, Ceylon, Elm, and Julia (in fact, a few of these seem closer to a production-ready product than Idris does). I assume most of these will be removed after an official 1.0 launch.