1−{-# LANGUAGE PatternGuards, OverloadedStrings #-}
1+{-# LANGUAGE PatternGuards, OverloadedStrings, FlexibleContexts #-}
3Copyright (C) 2008-2014 Andrea Rossato <andrea.rossato@ing.unitn.it>
3Copyright (C) 2008-2014 Andrea Rossato <andrea.rossato@ing.unitn.it>