Paragraph: Add a partial copy ctor that will get used in next commit.

git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@26000 a592a061-630c-0410-9148-cb99ea01b6c8

src/Paragraph.cpp

@@ -83,6 +83,8 @@ public:
 	Private(Paragraph * owner, Layout const & layout);
 	/// "Copy constructor"
 	Private(Private const &, Paragraph * owner);
+	/// Copy constructor from \p beg  to \p end
+	Private(Private const &, Paragraph * owner, pos_type beg, pos_type end);
 
 	///
 	void insertChar(pos_type pos, char_type c, Change const & change);
@@ -247,6 +249,43 @@ Paragraph::Private::Private(Private const & p, Paragraph * owner)
 }
 
 
+Paragraph::Private::Private(Private const & p, Paragraph * owner,
+	pos_type beg, pos_type end)
+	: owner_(owner), inset_owner_(p.inset_owner_), fontlist_(p.fontlist_), 
+	  params_(p.params_), changes_(p.changes_),
+	  begin_of_body_(p.begin_of_body_), words_(p.words_),
+	  layout_(p.layout_)
+{
+	id_ = paragraph_id++;
+	if (beg >= pos_type(p.text_.size()))
+		return;
+	text_ = p.text_.substr(beg, end - beg);
+	InsetList::const_iterator icit = p.insetlist_.begin();
+	InsetList::const_iterator iend = p.insetlist_.end();
+	for (; icit != iend; ++icit) {
+		if (icit->pos < beg)
+			continue;
+		if (icit->pos >= end)
+			break;
+		// Add a new entry in the insetlist_.
+		insetlist_.insert(icit->inset, icit->pos - beg);
+	}
+	FontList::const_iterator fcit = fontlist_.begin();
+	FontList::const_iterator fend = fontlist_.end();
+	for (; fcit != fend; ++fcit) {
+		if (fcit->pos() < beg)
+			continue;
+		if (fcit->pos() >= end) {
+			// Add last entry in the fontlist_.
+			fontlist_.set(text_.size() - 1, fcit->font());
+			break;
+		}
+		// Add a new entry in the fontlist_.
+		fontlist_.set(fcit->pos() - beg, fcit->font());
+	}
+}
+
+
 bool Paragraph::isChanged(pos_type start, pos_type end) const
 {
 	LASSERT(start >= 0 && start <= size(), /**/);
@@ -1060,6 +1099,14 @@ Paragraph::Paragraph(Paragraph const & par)
 }
 
 
+Paragraph::Paragraph(Paragraph const & par, pos_type beg, pos_type end)
+	: itemdepth(par.itemdepth),
+	d(new Paragraph::Private(*par.d, this, beg, end))
+{
+	registerWords();
+}
+
+
 Paragraph & Paragraph::operator=(Paragraph const & par)
 {
 	// needed as we will destroy the private part before copying it

src/Paragraph.h

@@ -89,6 +89,9 @@ public:
 	Paragraph();
 	///
 	Paragraph(Paragraph const &);
+	/// Partial copy constructor.
+	/// Copy the Paragraph contents from \p beg to \p end (without end).
+	Paragraph(Paragraph const & par, pos_type beg, pos_type end);
 	///
 	Paragraph & operator=(Paragraph const &);
 	///