Fix compiler errors

Author: vincentlaucsb

include/internal/common.hpp

@@ -259,6 +259,18 @@ namespace csv {
         class lazy_shared_ptr {
         public:
             lazy_shared_ptr() = default;
+            lazy_shared_ptr(const lazy_shared_ptr&) = delete;
+            lazy_shared_ptr& operator=(const lazy_shared_ptr&) = delete;
+
+            lazy_shared_ptr(lazy_shared_ptr&& other) noexcept : value_(std::move(other.value_)) {}
+
+            lazy_shared_ptr& operator=(lazy_shared_ptr&& other) noexcept {
+                if (this != &other) {
+                    value_ = std::move(other.value_);
+                }
+
+                return *this;
+            }
 
             template<typename Factory>
             T& get_or_create(Factory&& factory) const {

include/internal/data_frame.hpp

@@ -68,14 +68,13 @@ namespace csv {
 
     class DataFrameCell : public CSVField {
     public:
-        DataFrameCell() : CSVField(csv::string_view()), row(nullptr), row_edits(nullptr), col_index(0), can_mutate(false) {}
+        DataFrameCell() : CSVField(csv::string_view()), row_edits(nullptr), col_index(0), can_mutate(false) {}
 
         DataFrameCell(
             const CSVRow* _row,
             std::unordered_map<size_t, std::string>* _row_edits,
             size_t _col_index
         ) : CSVField(current_value(_row, _row_edits, _col_index)),
-            row(_row),
             row_edits(_row_edits),
             col_index(_col_index),
             can_mutate(true) {}
@@ -85,7 +84,6 @@ namespace csv {
             const std::unordered_map<size_t, std::string>* _row_edits,
             size_t _col_index
         ) : CSVField(current_value(_row, _row_edits, _col_index)),
-            row(_row),
             row_edits(_row_edits),
             col_index(_col_index),
             can_mutate(false) {}
@@ -121,7 +119,6 @@ namespace csv {
             return *this;
         }
 
-        const CSVRow* row;
         const std::unordered_map<size_t, std::string>* row_edits;
         size_t col_index;
         bool can_mutate;