On 17 avr. 2014, at 21:20, Edward Kmett <ekmett@gmail.com> wrote:

Consensus was achieved to add it as an infixl 1 & operator to Data.Function, but not to Prelude,so we just need to put in the patch and you'll see it in GHC 7.10.

Why '&' and not '#', for example?  I have an empression that '&' often comes in pair with '|' for Boolean operations.

Alexey.