true
[http://try.frege-lang.org/ Try] this language on [http://try.frege-lang.org/ frege-lang.org].
'''Frege''' is a purely functional programming language with non-strict semantics, strongly influenced by Haskell, but targeting the JVM, and deviates from Haskell in ways which make it easier to interoperate with Java.
Frege source files use the extension .fr. Frege is similar enough to Haskell that haskell-mode can be used for editing Frege source files, for example by putting this line in your .emacs:
(add-to-list 'auto-mode-alist '("\\.fr$" . haskell-mode))