unique_vector.h | Explore in Territory

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#ifndef SRC_TINT_UTILS_CONTAINERS_UNIQUE_VECTOR_H_
#define SRC_TINT_UTILS_CONTAINERS_UNIQUE_VECTOR_H_

#include <cstddef>
#include <functional>
#include <unordered_set>
#include <utility>
#include <vector>

#include "src/tint/utils/containers/hashset.h"
#include "src/tint/utils/containers/vector.h"

namespace tint {

/// UniqueVector is an ordered container that only contains unique items.
/// Attempting to add a duplicate is a no-op.
template <typename T, size_t N, typename HASH = Hasher<T>, typename EQUAL = std::equal_to<T>>
struct UniqueVector {
    /// STL-friendly alias to T. Used by gmock.
    using value_type = T;

    /// Constructor
    UniqueVector() = default;

    /// Constructor
    /// @param v the vector to construct this UniqueVector with. Duplicate
    /// elements will be removed.
    explicit UniqueVector(std::vector<T>&& v) { … }

    /// Add appends the item to the end of the vector, if the vector does not
    /// already contain the given item.
    /// @param item the item to append to the end of the vector
    /// @returns true if the item was added, otherwise false.
    bool Add(const T& item) { … }

    /// Removes @p count elements from the vector
    /// @param start the index of the first element to remove
    /// @param count the number of elements to remove
    void Erase(size_t start, size_t count = 1) { … }

    /// @returns true if the vector contains `item`
    /// @param item the item
    bool Contains(const T& item) const { … }

    /// @param i the index of the element to retrieve
    /// @returns the element at the index `i`
    T& operator[](size_t i) { … }

    /// @param i the index of the element to retrieve
    /// @returns the element at the index `i`
    const T& operator[](size_t i) const { … }

    /// @returns true if the vector is empty
    bool IsEmpty() const { … }

    /// Removes all elements from the vector
    void Clear() { … }

    /// @returns the number of items in the vector
    size_t Length() const { … }

    /// @returns the pointer to the first element in the vector, or nullptr if the vector is empty.
    const T* Data() const { … }

    /// @returns an iterator to the beginning of the vector
    auto begin() const { … }

    /// @returns an iterator to the end of the vector
    auto end() const { … }

    /// @returns an iterator to the beginning of the reversed vector
    auto rbegin() const { … }

    /// @returns an iterator to the end of the reversed vector
    auto rend() const { … }

    /// @returns a reference to the internal vector
    operator VectorRef<T>() const { return vector; }

    /// @returns the std::move()'d vector.
    /// @note The UniqueVector must not be used after calling this method
    VectorRef<T> Release() { … }

    /// Pre-allocates `count` elements in the vector and set
    /// @param count the number of elements to pre-allocate
    void Reserve(size_t count) { … }

    /// Removes the last element from the vector
    /// @returns the popped element
    T Pop() { … }

    /// Removes the last element from the vector if it is equal to @p value
    /// @param value the value to pop if it is at the back of the vector
    /// @returns true if the value was popped, otherwise false
    bool TryPop(T value) { … }

  private:
    Vector<T, N> vector;
    Hashset<T, N, HASH, EQUAL> set;
};

}  // namespace tint

#endif  // SRC_TINT_UTILS_CONTAINERS_UNIQUE_VECTOR_H_
chromium/third_party/dawn/src/tint/utils/containers/unique_vector.h
