Before this commit, the explicit version @f of a constant f with implicit arguments as not definitionally equal to f.
For example, if we had
variable f {A : Type} : A -> Bool
Then, the definition of @f was
definition @f (A : Type) (a : A) : Bool := f A a
This definition is equivalent to
fun A a, f A a
which is not definitionally equal to
f
since definitionally equality in Lean ignores Eta conversion.
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>