diff --git a/src/contractor.jl b/src/contractor.jl
index dbca4d0..3ee5150 100644
--- a/src/contractor.jl
+++ b/src/contractor.jl
@@ -39,10 +39,7 @@ function Base.show(io::IO, C::Contractor{N,Nout,F1,F2,ex}) where {N,Nout,F1,F2,e
     print(io, "  - expression: $(C.expression)")
 end
 
-function (C::Contractor{N,Nout,F1,F2,ex})(X::IntervalBox{N,T}) where {N,Nout,F1,F2,ex,T}
-    return C.forward(X)[1]
-end
-
+    (C::Contractor)(X) = C.forward(X)[1]
 
 function (C::Contractor{N,Nout,F1,F2,ex})(
     A::IntervalBox{Nout,T}, X::IntervalBox{N,T}) where {N,Nout,F1,F2,ex,T}
diff --git a/test/runtests.jl b/test/runtests.jl
index 21e5047..4785af5 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -20,6 +20,8 @@ end
     X =IntervalBox(-1..1,2)
     @test C(X) == 0..2
 
+    @test C((1,2)) == 5
+
 end
 
 @testset "Contractor without using macro" begin