implement more and more missing member functions of nfc_string.

src/nfc.cc

@@ -573,7 +573,6 @@ bool UTF<CharT>::is_safe_NFC_start(std::basic_string_view<CharT> s)
 }
 
 
-
 template<class CharT>
 IsNFC UTF<CharT>::isNFC_quick_check(std::basic_string_view<CharT> s)
 {
@@ -730,6 +729,44 @@ UTF<CharT>::nfc_string& UTF<CharT>::nfc_string::assign(String&& src)
 	return *this;
 }
 
+template<class CharT>
+typename
+UTF<CharT>::nfc_string& UTF<CharT>::nfc_string::push_back(CharT c)
+{
+	s += c;
+	if( !is_safe_NFC_start(StringView{&c, 1}) )
+	{
+		normalize();
+	}
+	return *this;
+}
+
+template<class CharT>
+typename
+UTF<CharT>::nfc_string& UTF<CharT>::nfc_string::operator+=(StringView sv)
+{
+	const String& sv_nfc = toNFC(sv);
+	s += sv_nfc;
+	if( !is_safe_NFC_start(sv_nfc) )
+	{
+		normalize();
+	}
+	return *this;
+}
+
+template<class CharT>
+typename
+UTF<CharT>::nfc_string& UTF<CharT>::nfc_string::operator+=(const UTF<CharT>::nfc_string& ns)
+{
+	s += ns.get();
+	if( !is_safe_NFC_start(ns) )
+	{
+		normalize();
+	}
+	return *this;
+}
+
+
 
 // convenience function to avoid ::strdup(pEp::toNFC<char>(text).c_str());
 // and unecessary temporary std::string etc.

src/nfc.hh

@@ -123,6 +123,8 @@ public:
 		/// read-only: shares representation
 		operator const String&() const noexcept { return s; }
 		
+		const String& get() const noexcept { return s;}
+		
 		/// read write: copy content
 		operator String() const { return s; }
 		
@@ -177,13 +179,13 @@ public:
 			return *this;
 		}
 		
-		nfc_string& operator+=(const StringView& s);
+		nfc_string& operator+=(StringView s);
 		
 		/// optimization possible to avoid re-normalization in most cases.
 		nfc_string& operator+=(const nfc_string& s);
 		
 		/// optimization possible to avoid re-normalization in most cases.
-		nfc_string& operator+=(CharT c);
+		nfc_string& operator+=(CharT c) { push_back(c); return *this; }
 		
 		/// delegates all 9 compare() overloads to s
 		template<typename... Args>