This package provides a canonical anonymous 1-tuple type missing from Haskell
for attaching typeclass instances.
NOTE: There is also the </package/OneTuple OneTuple package> which by using a
boxed 'data'-type provides a 1-tuple type which has laziness properties which
are more faithful to the ones of Haskell's native tuples; whereas the primary
purpose of 'Only' is to provide the traditionally so named type-wrapper for
attaching typeclass instances.
