Use function return value directly to eliminate variables

example/37_permute/common.hpp

@@ -289,23 +289,20 @@ is_valid_indices(const Shape& shape, const Indices& indices)
     return true;
 }
 
-template <typename Shape, typename Axes, typename OutputIterator>
-inline std::enable_if_t<detail::is_random_access_range_v<Shape> &&
-                            detail::is_sized_range_v<Shape> && detail::is_sized_range_v<Axes> &&
-                            detail::is_output_iterator_v<OutputIterator>,
-                        OutputIterator>
-transpose_shape(const Shape& shape, const Axes& axes, OutputIterator iter)
+template <std::size_t Size>
+std::array<std::size_t, Size> transpose(const std::array<std::size_t, Size>& shape,
+                                        const std::array<std::size_t, Size>& axes)
 {
-    using std::size;
-    assert(size(shape) == size(axes));
     assert(is_valid_shape(shape) && is_valid_axes(axes));
 
+    std::array<std::size_t, Size> transposed;
+    auto iter = std::begin(transposed);
     for(const auto axis : axes)
     {
         *iter++ = shape[axis];
     }
 
-    return iter;
+    return transposed;
 }
 
 auto extend_shape(const Problem::Shape& shape, std::size_t new_dim)

example/37_permute/run_permute_bundle_example.inc

@@ -12,8 +12,7 @@ bool run_permute_bundle(const Problem& problem)
     const auto& input_bundle_shape = problem.shape;
     const auto& input_bundle_axes  = problem.axes;
 
-    ck::remove_cvref_t<decltype(input_bundle_shape)> output_bundle_shape;
-    transpose_shape(input_bundle_shape, input_bundle_axes, begin(output_bundle_shape));
+    const auto output_bundle_shape = transpose(input_bundle_shape, input_bundle_axes);
 
     Tensor<BundleType> input_bundle_tensor(input_bundle_shape);
     Tensor<BundleType> output_bundle_tensor(output_bundle_shape);
@@ -66,18 +65,16 @@ bool run_permute_bundle(const Problem& problem)
     output_device_buf.FromDevice(data(output_bundle_tensor));
 
     // extend tensor shape from [N, H, W] to [N, H, W, NumElemsInBundle]
+    //               axes  from [0, 2, 1] to [0, 2, 1, 3]
     const auto input_shape = extend_shape(input_bundle_shape, NumElemsInBundle);
     const auto input_axes  = extend_axes(input_bundle_axes);
 
-    ck::remove_cvref_t<decltype(input_shape)> output_shape;
-    transpose_shape(input_shape, input_axes, begin(output_shape));
-
     Tensor<DataType> input_tensor(input_shape);
     std::memcpy(data(input_tensor),
                 data(input_bundle_tensor),
                 input_bundle_tensor.GetElementSpaceSizeInBytes());
 
-    Tensor<DataType> output_tensor(output_shape);
+    Tensor<DataType> output_tensor(transpose(input_shape, input_axes));
     if(!host_permute(input_tensor, input_axes, PassThrough{}, output_tensor))
     {
         return false;

example/37_permute/run_permute_element_example.inc

@@ -10,8 +10,7 @@ bool run_permute_element(const Problem& problem)
     const auto& input_shape = problem.shape;
     const auto& input_axes  = problem.axes;
 
-    ck::remove_cvref_t<decltype(input_shape)> output_shape;
-    transpose_shape(input_shape, input_axes, begin(output_shape));
+    const auto output_shape = transpose(input_shape, input_axes);
 
     Tensor<InDataType> input_tensor(input_shape);
     Tensor<OutDataType> output_tensor(output_shape);