zip on 1.0

Author: mcabbott

src/tangent_types/abstract_zero.jl

@@ -81,7 +81,7 @@ function _promote_vectors(x::AbstractVector, y::AbstractVector)
     if isconcretetype(T)
         return convert(T, x), convert(T, y)
     else
-        short = map(first ∘ promote, x, y)
+        short = map(Base.splat(first ∘ promote), zip(x, y))
         return convert(typeof(short), x), convert(typeof(short), y)
     end
 end