[Haskell-cafe] Is a type synonym declaration really a synonym ?

[alpheccar]

>
> Type synonyms are implicitly parenthetized, and your :+: is
> non-associative.  Compare:

Thank you. I did not know that. But, I suspected it after my failed  
experiments. So, I'll have to change my implementation and find a  
workaround if I can :-(

Christophe.