1 files changed, 7 insertions, 6 deletions

diff --git a/include/unicode.h b/include/unicode.h
index 2969aa0..b90ed15 100644
--- a/include/unicode.h
+++ b/include/unicode.h
@@ -43,9 +43,9 @@ namespace {
    return value;
   }
 
-  std::u8string::iterator iterator;
+  std::u8string::const_iterator iterator;
 
-  std::u8string::iterator end_iterator;
+  std::u8string::const_iterator end_iterator;
   value_type value{};
  };
 
@@ -71,6 +71,7 @@ namespace {
   reference operator=(const char32_t& value)
   {
    s.push_back(0); // TODO
+   return *this;
   }
 
   std::u16string& s;
@@ -81,14 +82,14 @@ namespace {
   return utf16_back_insert_iterator(s);
  }
 
- utf8_iterator utf8_begin(std::u8string& s)
+ utf8_iterator utf8_begin(const std::u8string& s)
  {
-  return utf8_iterator{s.begin(), s.end()};
+  return utf8_iterator{s.cbegin(), s.cend()};
  }
 
- utf8_iterator utf8_end(std::u8string& s)
+ utf8_iterator utf8_end(const std::u8string& s)
  {
-  return utf8_iterator{s.end(), s.end()};
+  return utf8_iterator{s.cend(), s.cend()};
  }
 
 } // namespace