now the non-const String::operator[] returns a Char class instead of a

primitive

CMakeLists.txt

@@ -10,5 +10,5 @@ find_package(GTest REQUIRED)
 include_directories(${GTEST_INCLUDE_DIRS})
 link_libraries(${GTEST_BOTH_LIBRARIES})
 
-set(SOURCE_FILES String.cpp String.h StringValue.cpp StringValue.h test.cpp)
+set(SOURCE_FILES String.cpp String.h StringValue.cpp StringValue.h Char.cpp Char.h test.cpp)
 add_executable(cpp11NHF1_refcountedString ${SOURCE_FILES})

String.cpp

@@ -1,4 +1,5 @@
 #include "String.h"
+#include "Char.h"
 #include <cstring>
 #include <memory>
 
@@ -114,9 +115,9 @@ const char& String::operator[](size_t index) const
 }
 
 // reuse const operator[]
-char& String::operator[](size_t index)
+Char String::operator[](size_t index)
 {
-    return const_cast<char&>(const_cast<const String*>(this)->operator[](index));
+    return Char(_str->index_of(&const_cast<char&>(const_cast<const String*>(this)->operator[](index))), *this);
 }
 
 size_t String::size() const

String.h

@@ -1,6 +1,8 @@
 #pragma once
 #include <iostream>
 #include "StringValue.h"
+#include "Char.h"
+class Char;
 
 
 
@@ -30,12 +32,13 @@ public:
     String& operator+=(char);
     bool operator==(const String&) const;
     const char& operator[](size_t) const;
-    char& operator[](size_t);
+    Char operator[](size_t);
 
     size_t size() const;    // does not include null-terminator
     const char* c_str() const;
 
     friend std::istream& operator>>(std::istream&, String&);
+    friend class Char;
 };
 
 std::ostream& operator<<(std::ostream&, const String&);