scratch_buffer: Add member types to ScratchBuffer

Allows for implicit conversion to std::span<T>.

src/common/scratch_buffer.h

@@ -5,7 +5,6 @@
 
 #include <iterator>
 
-#include "common/concepts.h"
 #include "common/make_unique_for_overwrite.h"
 
 namespace Common {
@@ -19,15 +18,22 @@ namespace Common {
 template <typename T>
 class ScratchBuffer {
 public:
-    using iterator = T*;
-    using const_iterator = const T*;
-    using value_type = T;
     using element_type = T;
-    using iterator_category = std::contiguous_iterator_tag;
+    using value_type = T;
+    using size_type = size_t;
+    using difference_type = std::ptrdiff_t;
+    using pointer = T*;
+    using const_pointer = const T*;
+    using reference = T&;
+    using const_reference = const T&;
+    using iterator = pointer;
+    using const_iterator = const_pointer;
+    using iterator_category = std::random_access_iterator_tag;
+    using iterator_concept = std::contiguous_iterator_tag;
 
     ScratchBuffer() = default;
 
-    explicit ScratchBuffer(size_t initial_capacity)
+    explicit ScratchBuffer(size_type initial_capacity)
         : last_requested_size{initial_capacity}, buffer_capacity{initial_capacity},
           buffer{Common::make_unique_for_overwrite<T[]>(initial_capacity)} {}
 
@@ -39,7 +45,7 @@ public:
 
     /// This will only grow the buffer's capacity if size is greater than the current capacity.
     /// The previously held data will remain intact.
-    void resize(size_t size) {
+    void resize(size_type size) {
         if (size > buffer_capacity) {
             auto new_buffer = Common::make_unique_for_overwrite<T[]>(size);
             std::move(buffer.get(), buffer.get() + buffer_capacity, new_buffer.get());
@@ -51,7 +57,7 @@ public:
 
     /// This will only grow the buffer's capacity if size is greater than the current capacity.
     /// The previously held data will be destroyed if a reallocation occurs.
-    void resize_destructive(size_t size) {
+    void resize_destructive(size_type size) {
         if (size > buffer_capacity) {
             buffer_capacity = size;
             buffer = Common::make_unique_for_overwrite<T[]>(buffer_capacity);
@@ -59,43 +65,43 @@ public:
         last_requested_size = size;
     }
 
-    [[nodiscard]] T* data() noexcept {
+    [[nodiscard]] pointer data() noexcept {
         return buffer.get();
     }
 
-    [[nodiscard]] const T* data() const noexcept {
+    [[nodiscard]] const_pointer data() const noexcept {
         return buffer.get();
     }
 
-    [[nodiscard]] T* begin() noexcept {
+    [[nodiscard]] iterator begin() noexcept {
         return data();
     }
 
-    [[nodiscard]] const T* begin() const noexcept {
+    [[nodiscard]] const_iterator begin() const noexcept {
         return data();
     }
 
-    [[nodiscard]] T* end() noexcept {
+    [[nodiscard]] iterator end() noexcept {
         return data() + last_requested_size;
     }
 
-    [[nodiscard]] const T* end() const noexcept {
+    [[nodiscard]] const_iterator end() const noexcept {
         return data() + last_requested_size;
     }
 
-    [[nodiscard]] T& operator[](size_t i) {
+    [[nodiscard]] reference operator[](size_type i) {
         return buffer[i];
     }
 
-    [[nodiscard]] const T& operator[](size_t i) const {
+    [[nodiscard]] const_reference operator[](size_type i) const {
         return buffer[i];
     }
 
-    [[nodiscard]] size_t size() const noexcept {
+    [[nodiscard]] size_type size() const noexcept {
         return last_requested_size;
     }
 
-    [[nodiscard]] size_t capacity() const noexcept {
+    [[nodiscard]] size_type capacity() const noexcept {
         return buffer_capacity;
     }
 
@@ -106,8 +112,8 @@ public:
     }
 
 private:
-    size_t last_requested_size{};
+    size_type last_requested_size{};
-    size_t buffer_capacity{};
+    size_type buffer_capacity{};
     std::unique_ptr<T[]> buffer{};
 };