Update 'ideas.md'

ideas.md

@@ -57,12 +57,13 @@ In the real-world, working with external data in file systems and databases is o
 - Haskell
 - Idris
 - Agda
+- Cayenne (first dependent language)
 - Python: Indentation syntax
 - Go
 - Rust: Trait naming
 - Erlang
 
-Languages to look into: Lisp, ML, Clojure, F#, Scala, Nix, Nim
+Languages to look into: Lisp (homoiconicity?), (S)ML, Clojure, F#, Scala, Nix, Nim, Elm
 
 
 ## Meta-Usability