chromium/third_party/dawn/src/tint/utils/containers/slice.h

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#ifndef SRC_TINT_UTILS_CONTAINERS_SLICE_H_
#define SRC_TINT_UTILS_CONTAINERS_SLICE_H_

#include <array>
#include <cstdint>
#include <iterator>

#include "src/tint/utils/ice/ice.h"
#include "src/tint/utils/memory/bitcast.h"
#include "src/tint/utils/rtti/castable.h"
#include "src/tint/utils/traits/traits.h"

namespace tint {

/// A type used to indicate an empty array.
struct EmptyType { … };

/// An instance of the EmptyType.
static constexpr EmptyType Empty;

/// Mode enumerator for ReinterpretSlice
enum class ReinterpretMode { … };

namespace detail {

ConstRemoved;

/// Private implementation of tint::CanReinterpretSlice.
/// Specialized for the case of TO equal to FROM, which is the common case, and avoids inspection of
/// the base classes, which can be troublesome if the slice is of an incomplete type.
template <ReinterpretMode MODE, typename TO, typename FROM>
struct CanReinterpretSlice { … };

/// Specialization of 'CanReinterpretSlice' for when TO and FROM are equal types.
CanReinterpretSlice<MODE, T, T>;

}  // namespace detail

/// Evaluates whether a `Slice<FROM>` and be reinterpreted as a `Slice<TO>`.
/// Slices can be reinterpreted if:
///  * TO has the same or more 'constness' than FROM.
///  * And either:
///  * `FROM` and `TO` are pointers to the same type
///  * `FROM` and `TO` are pointers to CastableBase (or derived), and the pointee type of `TO` is of
///     the same type as, or is an ancestor of the pointee type of `FROM`.
CanReinterpretSlice;

/// A slice represents a contigious array of elements of type T.
template <typename T>
struct Slice { … };

/// Deduction guide for Slice from c-array
/// @param elements the input elements
template <typename T, size_t N>
Slice(T (&elements)[N]) -> Slice<T>;

}  // namespace tint

#endif  // SRC_TINT_UTILS_CONTAINERS_SLICE_H_