ArrayView, adding ctor for fixed-size views of std::array.
This CL allows to reduce the code required to create fixed-size ArrayView
objects for std::array instances. Instead of passing .data() and .size(),
it is now sufficient to pass the std::array instance. When instancing an
array view with variable size, a different ctor is called.
Bug: webrtc:9076
Change-Id: I4fe133b27cd12827ed0206d40184279fc3a196f5
Reviewed-on: https://webrtc-review.googlesource.com/76160
Commit-Queue: Alessio Bazzica <alessiob@webrtc.org>
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#23220}diff --git a/api/array_view.h b/api/array_view.h
index d951d0f..a9df84d 100644
--- a/api/array_view.h
+++ b/api/array_view.h
@@ -11,6 +11,7 @@
#ifndef API_ARRAY_VIEW_H_
#define API_ARRAY_VIEW_H_
+#include <array>
#include <algorithm>
#include <type_traits>
@@ -169,7 +170,7 @@
RTC_DCHECK_EQ(0, size);
}
- // Construct an ArrayView from an array.
+ // Construct an ArrayView from a C-style array.
template <typename U, size_t N>
ArrayView(U (&array)[N]) // NOLINT
: ArrayView(array, N) {
@@ -177,6 +178,16 @@
"Array size must match ArrayView size");
}
+ // (Only if size is fixed.) Construct an ArrayView with fixed size from an
+ // std::array instance. For an ArrayView with variable size, the used ctor is
+ // ArrayView(U& u) instead - i.e., the next one.
+ template <typename U,
+ size_t N,
+ typename std::enable_if<
+ Size == static_cast<std::ptrdiff_t>(N)>::type* = nullptr>
+ ArrayView(std::array<U, N>& u) // NOLINT
+ : ArrayView(u.data(), u.size()) {}
+
// (Only if size is fixed.) Construct an ArrayView from any type U that has a
// static constexpr size() method whose return value is equal to Size, and a
// data() method whose return value converts implicitly to T*. In particular,
