fix conversionwrapper

Author: jishnub

src/Operators/banded/Conversion.jl

@@ -126,9 +126,12 @@ Conversion(A::Space,B::Space,C::Space,D::Space...) =
 
 ==(A::ConversionWrapper,B::ConversionWrapper) = A.op==B.op
 
-function ConversionWrapper{D,R,T,O}(C::ConcreteConversion) where {D<:Space,R<:Space,T,O<:Operator{T}}
-    ConversionWrapper{D,R,T,O}(strictconvert(D,C.domainspace), strictconvert(R,C.rangespace),
-        strictconvert(O, C.op))
+function ConversionWrapper{D,R,T,O}(C::ConversionWrapper) where {D<:Space,R<:Space,T,O<:Operator{T}}
+    ConversionWrapper{D,R,T,O}(
+        strictconvert(D,C.domainspace),
+        strictconvert(R,C.rangespace),
+        strictconvert(O, C.op)
+    )
 end
 function Operator{T}(D::ConversionWrapper) where T
     BO=strictconvert(Operator{T},D.op)

test/runtests.jl

@@ -356,6 +356,10 @@ end
         ApproxFunBase.mul_coefficients!(Operator(2I), v)
         @test v ≈ Float64[2i^2 for i in 1:4]
     end
+    @testset "type parameter conversion" begin
+        C = Conversion(PointSpace(1:3), PointSpace(1:3));
+        @test typeof(C)(C) == C
+    end
 end
 
 @testset "RowVector" begin