From ead66c0679da1c7e774913143aaf3ce4be875621 Mon Sep 17 00:00:00 2001
From: Georg Baum <Georg.Baum@post.rwth-aachen.de>
Date: Sun, 8 Oct 2006 09:44:26 +0000
Subject: [PATCH] Add operator += for ASCII C strings and single ASCII chars

git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@15274 a592a061-630c-0410-9148-cb99ea01b6c8
---
 src/support/docstring.C | 31 +++++++++++++++++++++++++++++++
 src/support/docstring.h |  9 +++++++++
 2 files changed, 40 insertions(+)

diff --git a/src/support/docstring.C b/src/support/docstring.C
index 59ac6fedb7..ceffbc3832 100644
--- a/src/support/docstring.C
+++ b/src/support/docstring.C
@@ -40,6 +40,19 @@ docstring const from_ascii(std::string const & ascii)
 }
 
 
+std::string const to_ascii(docstring const & ucs4)
+{
+	int const len = ucs4.length();
+	std::string ascii;
+	ascii.resize(len);
+	for (int i = 0; i < len; ++i) {
+		BOOST_ASSERT(ucs4[i] < 0x80);
+		ascii[i] = static_cast<char>(ucs4[i]);
+	}
+	return ascii;
+}
+
+
 docstring const from_utf8(std::string const & utf8)
 {
 	std::vector<lyx::char_type> const ucs4 =
@@ -109,6 +122,24 @@ lyx::docstring operator+(char l, lyx::docstring const & r)
 }
 
 
+lyx::docstring operator+=(lyx::docstring & l, char const * r)
+{
+	for (char const * c = r; *c; ++c) {
+		BOOST_ASSERT(static_cast<unsigned char>(*c) < 0x80);
+		l.push_back(*c);
+	}
+	return l;
+}
+
+
+lyx::docstring operator+=(lyx::docstring & l, char r)
+{
+	BOOST_ASSERT(static_cast<unsigned char>(r) < 0x80);
+	l.push_back(r);
+	return l;
+}
+
+
 #if (!defined(HAVE_WCHAR_T) || SIZEOF_WCHAR_T != 4) && defined(__GNUC__)
 
 // gcc does not have proper locale facets for lyx::char_type if
diff --git a/src/support/docstring.h b/src/support/docstring.h
index 7b248f6ab1..1cff5109a0 100644
--- a/src/support/docstring.h
+++ b/src/support/docstring.h
@@ -28,6 +28,9 @@ docstring const from_ascii(char const *);
 /// Creates a docstring from a std::string of ASCII characters
 docstring const from_ascii(std::string const &);
 
+/// Creates a std::string of ASCII characters from a docstring
+std::string const to_ascii(docstring const &);
+
 /// Creates a docstring from a UTF8 string. This should go eventually.
 docstring const from_utf8(std::string const &);
 
@@ -60,6 +63,12 @@ lyx::docstring operator+(lyx::docstring const & l, char r);
 /// Concatenate a single ASCII character and a docstring
 lyx::docstring operator+(char l, lyx::docstring const & r);
 
+/// Append a C string of ASCII characters to a docstring
+lyx::docstring operator+=(lyx::docstring &, char const *);
+
+/// Append a single ASCII character to a docstring
+lyx::docstring operator+=(lyx::docstring & l, char r);
+
 
 #if SIZEOF_WCHAR_T != 4 && defined(__GNUC__) && defined(__GNUC_MINOR__) && __GNUC__ == 3 && __GNUC_MINOR__ < 4
 // Missing char_traits methods in gcc 3.3 and older. Taken from gcc 4.2svn.