]> git.lyx.org Git - lyx.git/blobdiff - src/mathed/math_cursor.C
cursor up/down behind scripts fixed
[lyx.git] / src / mathed / math_cursor.C
index ab7af81c4bb7ae79363bdffccaa13b13520b7f26..ca2b35904f9b371e1554971a37f62b03d1bc05e3 100644 (file)
@@ -24,6 +24,7 @@
 #include <cctype>
 
 #include "support/lstrings.h"
+#include "support/LAssert.h"
 #include "debug.h"
 #include "LColor.h"
 #include "Painter.h"
 #include "math_charinset.h"
 #include "math_deliminset.h"
 #include "math_matrixinset.h"
-#include "math_scopeinset.h"
 #include "math_scriptinset.h"
 #include "math_spaceinset.h"
+#include "math_specialcharinset.h"
 #include "math_parser.h"
 
+#define FILEDEBUG 0
+
 using std::endl;
 using std::min;
 using std::max;
+using std::swap;
 using std::isalnum;
 
-
 namespace {
 
 struct Selection
@@ -59,8 +62,9 @@ struct Selection
                if (i1.idx_ == i2.idx_)
                        data_.push_back(MathArray(i1.cell(), i1.pos_, i2.pos_));
                else {
-                       std::vector<int> indices = i1.par_->idxBetween(i1.idx_, i2.idx_);
-                       for (unsigned i = 0; i < indices.size(); ++i)
+                       std::vector<MathInset::idx_type> indices =
+                               (*i1.par_)->idxBetween(i1.idx_, i2.idx_);
+                       for (MathInset::idx_type i = 0; i < indices.size(); ++i)
                                data_.push_back(i1.cell(indices[i]));
                }
        }
@@ -70,10 +74,11 @@ struct Selection
                MathCursorPos i1;
                MathCursorPos i2;
                cursor.getSelection(i1, i2); 
-               if (i1.idx_ == i2.idx_)
+               if (i1.idx_ == i2.idx_) {
                        i1.cell().erase(i1.pos_, i2.pos_);
-               else {
-                       std::vector<int> indices = i1.par_->idxBetween(i1.idx_, i2.idx_);
+               } else {
+                       std::vector<MathInset::idx_type> indices =
+                               (*i1.par_)->idxBetween(i1.idx_, i2.idx_);
                        for (unsigned i = 0; i < indices.size(); ++i)
                                i1.cell(indices[i]).erase();
                }
@@ -82,7 +87,8 @@ struct Selection
 
        void paste(MathCursor & cursor) const
        {
-               cursor.insert(glue());
+               MathArray ar = glue();
+               cursor.paste(ar);
        }
 
        // glues selection to one cell
@@ -106,78 +112,97 @@ struct Selection
 Selection theSelection;
 
 
+#if FILEDEBUG
 std::ostream & operator<<(std::ostream & os, MathCursorPos const & p)
 {
-       os << "(par: " << p.par_ << " idx: " << p.idx_
-          << " pos: " << p.pos_ << ")";
+       os << "(par: " << p.par_ << " idx: " << p.idx_ << " pos: " << p.pos_ << ")";
        return os;
 }
+#endif
 
 }
 
 
-MathCursor::MathCursor(InsetFormulaBase * formula)
+MathCursor::MathCursor(InsetFormulaBase * formula, bool left)
        : formula_(formula), lastcode_(LM_TC_VAR), selection_(false)
 {
-       first();
+       left ? first() : last();
 }
 
 
-void MathCursor::pushLeft(MathInset * par)
+void MathCursor::push(MathAtom & t)
 {
+       //cerr << "Entering atom "; t->write(cerr, false); cerr << " left\n";
        MathCursorPos p;
-       p.par_ = par;
-       par->idxFirst(p.idx_, p.pos_);
+       p.par_ = &t;
        Cursor_.push_back(p);
 }
 
 
-void MathCursor::pushRight(MathInset * par)
+void MathCursor::pushLeft(MathAtom & t)
 {
+       //cerr << "Entering atom "; t->write(cerr, false); cerr << " left\n";
+       push(t);
+       t->idxFirst(idx(), pos());
+}
+
+
+void MathCursor::pushRight(MathAtom & t)
+{
+       //cerr << "Entering atom "; t->write(cerr, false); cerr << " right\n";
        posLeft();
-       MathCursorPos p;
-       p.par_ = par;
-       par->idxLast(p.idx_, p.pos_);
-       Cursor_.push_back(p);
+       push(t);
+       t->idxLast(idx(), pos());
 }
 
 
 bool MathCursor::popLeft()
 {
+       //cerr << "Leaving atom "; par()->write(cerr, false); cerr << " left\n";
        if (Cursor_.size() <= 1)
                return false;
+       //if (nextInset())
+       //      nextInset()->removeEmptyScripts();
        Cursor_.pop_back();
+       //if (nextAtom())
+       //      nextAtom()->removeEmptyScripts();
        return true;
 }
 
+
 bool MathCursor::popRight()
 {
+       //cerr << "Leaving atom "; par()->write(cerr, false); cerr << " right\n";
        if (Cursor_.size() <= 1)
                return false;
+       //if (nextInset())
+       //      nextInset()->removeEmptyScripts();
        Cursor_.pop_back();
+       //if (nextInset())
+       //      nextInset()->removeEmptyScripts();
        posRight();
        return true;
 }
 
 
-MathInset * MathCursor::parInset(int i) const
-{
-       return Cursor_[i].par_;
-}
-
 
+#if FILEDEBUG
 void MathCursor::dump(char const * what) const
 {
-       return;
-
        lyxerr << "MC: " << what << "\n";
        for (unsigned i = 0; i < Cursor_.size(); ++i)
                lyxerr << "  i: " << i 
-                       << " pos: " << Cursor_[i].pos_
+                       << " Cursor: pos: " << Cursor_[i].pos_
                        << " idx: " << Cursor_[i].idx_
                        << " par: " << Cursor_[i].par_ << "\n";
 
-       //lyxerr        << " sel: " << selection_ << " data: " << array() << "\n";
+       for (unsigned i = 0; i < Anchor_.size(); ++i)
+               lyxerr << "  i: " << i 
+                       << " Anchor: pos: " << Anchor_[i].pos_
+                       << " idx: " << Anchor_[i].idx_
+                       << " par: " << Anchor_[i].par_ << "\n";
+
+       lyxerr  << " sel: " << selection_ << "\n";
 }
 
 
@@ -185,7 +210,6 @@ void MathCursor::seldump(char const * str) const
 {
        //lyxerr << "SEL: " << str << ": '" << theSelection << "'\n";
        //dump("   Pos");
-       return;
 
        lyxerr << "\n\n\n=================vvvvvvvvvvvvv=======================   "
                <<  str << "\ntheSelection: " << selection_
@@ -200,40 +224,63 @@ void MathCursor::seldump(char const * str) const
        lyxerr << "\n===================^^^^^^^^^^^^=====================\n\n\n";
 }
 
+#else
+
+void MathCursor::seldump(char const *) const {}
+void MathCursor::dump(char const *) const {}
+
+#endif
+
 
 bool MathCursor::isInside(MathInset const * p) const
 {
        for (unsigned i = 0; i < Cursor_.size(); ++i) 
-               if (parInset(i) == p) 
+               if (Cursor_[i].par_->nucleus() == p) 
                        return true;
        return false;
 }
 
 
-bool MathCursor::openable(MathInset * p, bool sel, bool useupdown) const
+bool MathCursor::openable(MathAtom const & t, bool sel) const
 {
-       if (!p)
+       if (!t->isActive())
                return false;
 
-       if (!(p->isActive() || (useupdown && p->isScriptInset())))
+       if (t->asScriptInset())
                return false;
 
        if (sel) {
                // we can't move into anything new during selection
                if (Cursor_.size() == Anchor_.size())
                        return false;
-               if (p != Anchor_[Cursor_.size()].par_)
+               if (&t != Anchor_[Cursor_.size()].par_)
                        return false;
        }
        return true;
 }
 
 
+bool MathCursor::positionable(MathAtom const & t, int x, int y) const
+{
+       if (selection_) {
+               // we can't move into anything new during selection
+               if (Cursor_.size() == Anchor_.size())
+                       return 0;
+               //if (t != Anchor_[Cursor_.size()].par_)
+               //      return 0;
+       }
+
+       return t->nargs() && t->covers(x, y);
+}
+
+
 bool MathCursor::posLeft()
 {
        if (pos() == 0)
                return false;
+
        --pos();
+
        return true;
 }
 
@@ -242,7 +289,9 @@ bool MathCursor::posRight()
 {
        if (pos() == size())
                return false;
+
        ++pos();
+
        return true;
 }
 
@@ -258,9 +307,8 @@ bool MathCursor::left(bool sel)
        selHandle(sel);
        lastcode_ = LM_TC_VAR;
 
-       MathInset * p = prevInset();
-       if (openable(p, sel, false)) {
-               pushRight(p);
+       if (hasPrevAtom() && openable(prevAtom(), sel)) {
+               pushRight(prevAtom());
                return true;
        } 
        
@@ -279,9 +327,8 @@ bool MathCursor::right(bool sel)
        selHandle(sel);
        lastcode_ = LM_TC_VAR;
 
-       MathInset * p = nextInset();
-       if (openable(p, sel, false)) {
-               pushLeft(p);
+       if (hasNextAtom() && openable(nextAtom(), sel)) {
+               pushLeft(nextAtom());
                return true;
        }
 
@@ -292,7 +339,7 @@ bool MathCursor::right(bool sel)
 void MathCursor::first()
 {
        Cursor_.clear();
-       pushLeft(outerPar());
+       pushLeft(formula_->par());
 }
 
 
@@ -305,53 +352,52 @@ void MathCursor::last()
 
 void MathCursor::setPos(int x, int y)
 {
-       dump("setPos 1");
+       //dump("setPos 1");
        //lyxerr << "MathCursor::setPos x: " << x << " y: " << y << "\n";
 
        macroModeClose();
        lastcode_ = LM_TC_VAR;
        first();
 
-       cursor().par_  = outerPar();
+       cursor().par_  = &formula_->par();
 
        while (1) {
-               idx() = -1;
-               cursor().pos_ = -1;
-               //lyxerr << "found idx: " << idx_ << " cursor: " << pos()  << "\n";
+               idx() = 0;
+               cursor().pos_ = 0;
+               //lyxerr << "found idx: " << idx() << " cursor: " << pos()  << "\n";
                int distmin = 1 << 30; // large enough
-               for (int i = 0; i < par()->nargs(); ++i) {
+               for (unsigned int i = 0; i < par()->nargs(); ++i) {
                        MathXArray const & ar = par()->xcell(i);
                        int x1 = x - ar.xo();
                        int y1 = y - ar.yo();
-                       int c  = ar.x2pos(x1);
+                       MathXArray::size_type c  = ar.x2pos(x1);
                        int xx = abs(x1 - ar.pos2x(c));
                        int yy = abs(y1);
                        //lyxerr << "idx: " << i << " xx: " << xx << " yy: " << yy
                        //      << " c: " << c  << " xo: " << ar.xo() << "\n";
                        if (yy + xx <= distmin) {
-                               distmin        = yy + xx;
-                               idx()  = i;
-                               pos()  = c;
+                               distmin = yy + xx;
+                               idx()   = i;
+                               pos()   = c;
                        }
                }
                //lyxerr << "found idx: " << idx() << " cursor: "
                //      << pos()  << "\n";
-               MathInset * n = nextInset();
-               MathInset * p = prevInset();
-               if (openable(n, selection_, true) && n->covers(x, y))
-                       pushLeft(n);
-               else if (openable(p, selection_, true) && p->covers(x, y))
-                       pushRight(p);
+               if (hasNextAtom() && positionable(nextAtom(), x, y))
+                       pushLeft(nextAtom());
+               else if (hasPrevAtom() && positionable(prevAtom(), x, y))
+                       pushRight(prevAtom());
                else 
                        break;
        }
-       dump("setPos 2");
+       //dump("setPos 2");
 }
 
 
-void MathCursor::home()
+void MathCursor::home(bool sel)
 {
        dump("home 1");
+       selHandle(sel);
        macroModeClose();
        lastcode_ = LM_TC_VAR;
        if (!par()->idxHome(idx(), pos())) 
@@ -360,9 +406,10 @@ void MathCursor::home()
 }
 
 
-void MathCursor::end()
+void MathCursor::end(bool sel)
 {
        dump("end 1");
+       selHandle(sel);
        macroModeClose();
        lastcode_ = LM_TC_VAR;
        if (!par()->idxEnd(idx(), pos()))
@@ -377,38 +424,40 @@ void MathCursor::plainErase()
 }
 
 
+void MathCursor::plainInsert(MathAtom const & t)
+{
+       array().insert(pos(), t);
+       ++pos();
+}
+
+
 void MathCursor::insert(char c, MathTextCodes t)
 {
        //lyxerr << "inserting '" << c << "'\n";
-       array().insert(pos(), new MathCharInset(c, t));
-       posRight();
+       plainInsert(MathAtom(new MathCharInset(c, t)));
 }
 
 
-void MathCursor::insert(MathInset * p)
+void MathCursor::insert(MathAtom const & t)
 {
        macroModeClose();
 
        if (selection_) {
-               if (p->nargs())
+               if (t->nargs())
                        selCut();
                else
                        selDel();
        }
 
-       array().insert(pos(), p);
-       posRight();
+       plainInsert(t);
 }
 
 
-void MathCursor::niceInsert(MathInset * p
+void MathCursor::niceInsert(MathAtom const & t
 {
-       if (!p) {
-               lyxerr << "should not happen\n";
-               return;
-       }
        selCut();
-       insert(p);
+       insert(t); // inserting invalidates the pointer!
+       MathAtom const & p = prevAtom();
        if (p->nargs()) {
                posLeft();
                right();  // do not push for e.g. MathSymbolInset
@@ -429,30 +478,42 @@ void MathCursor::insert(MathArray const & ar)
 }
 
 
+void MathCursor::paste(MathArray const & ar)
+{
+       Anchor_ = Cursor_;
+       selection_ = true;
+       array().insert(pos(), ar);
+       pos() += ar.size();
+}
+
+
 void MathCursor::backspace()
 {
-       if (inMacroMode()) {
-               left();
+       if (pos() == 0) {
+               pullArg(false);
                return;
-       }
+       }       
 
-       if (posLeft()) {
-               plainErase();
+       if (selection_) {
+               selDel();
                return;
        }
 
-       if (size()) {
-               pullArg(false);
-               return;
+       MathScriptInset * p = prevAtom()->asScriptInset();
+       if (p) {
+               p->removeScript(p->hasUp());
+               // Don't delete if there is anything left 
+               if (p->hasUp() || p->hasDown())
+                       return;
        }
 
-       erase();
+       --pos();
+       plainErase();
 }
 
 
 void MathCursor::erase()
 {
-       dump("erase 1");
        if (inMacroMode())
                return;
 
@@ -462,7 +523,7 @@ void MathCursor::erase()
        }
 
        // delete empty cells if necessary
-       if (pos() == 0 && array().empty()) {
+       if (array().empty()) {
                bool popit;
                bool removeit;
                par()->idxDelete(idx(), popit, removeit);
@@ -471,10 +532,18 @@ void MathCursor::erase()
                return;
        }
 
-       if (pos() < size())
-               plainErase();
+       if (pos() == size())
+               return;
 
-       dump("erase 2");
+       MathScriptInset * p = nextAtom()->asScriptInset();
+       if (p) {
+               p->removeScript(p->hasUp());
+               // Don't delete if there is anything left 
+               if (p->hasUp() || p->hasDown())
+                       return;
+       }
+
+       plainErase();
 }
 
 
@@ -498,31 +567,26 @@ bool MathCursor::up(bool sel)
        macroModeClose();
        selHandle(sel);
 
-       if (selection_)
-               return goUp();
-
-       // check whether we could move into an inset on the right or on the left
-       MathInset * p = nextInset();
-       if (p) {
-               int idxx, poss;
-               if (p->idxFirstUp(idxx, poss)) {
-                       pushLeft(p);
-                       idx() = idxx;
-                       pos() = poss;
-                       dump("up 3");
-                       return true;
+       if (!selection_) {
+               // check whether we could move into a superscript 
+               if (hasPrevAtom()) {
+                       MathAtom & p = prevAtom();
+                       if (p->asScriptInset() && p->asScriptInset()->hasUp()) {
+                               pushRight(p);
+                               idx() = 1;
+                               pos() = size();
+                               return true;
+                       }
                }
-       }
 
-       p = prevInset();
-       if (p) {
-               int idxx, poss;
-               if (p->idxLastUp(idxx, poss)) {
-                       pushRight(p);
-                       idx() = idxx;
-                       pos() = poss;
-                       dump("up 4");
-                       return true;
+               if (hasNextAtom()) {
+                       MathAtom & n = nextAtom();
+                       if (n->asScriptInset() && n->asScriptInset()->hasUp()) {
+                               pushLeft(n);
+                               idx() = 1;
+                               pos() = 0;
+                               return true;
+                       }
                }
        }
 
@@ -536,33 +600,26 @@ bool MathCursor::down(bool sel)
        macroModeClose();
        selHandle(sel);
 
-       if (selection_) 
-               return goDown();
-
-       // check whether we could move into an inset on the right or on the left
-       MathInset * p = nextInset();
-       if (p) {
-               int idxx = 0;
-               int poss = 0;
-               if (p->idxFirstDown(idxx, poss)) {
-                       pushLeft(p);
-                       idx() = idxx;
-                       pos() = poss;
-                       dump("Down 3");
-                       return true;
+       if (!selection_) {
+               // check whether we could move into a subscript 
+               if (hasPrevAtom()) {
+                       MathAtom & p = prevAtom();
+                       if (p->asScriptInset() && p->asScriptInset()->hasDown()) {
+                               pushRight(p);
+                               idx() = 0;
+                               pos() = size();
+                               return true;
+                       }
                }
-       }
 
-       p = prevInset();
-       if (p) {
-               int idxx = 0;
-               int poss = 0;
-               if (p->idxLastDown(idxx, poss)) {
-                       pushRight(p);
-                       idx() = idxx;
-                       pos() = poss;
-                       dump("Down 4");
-                       return true;
+               if (hasNextAtom()) {
+                       MathAtom & n = nextAtom();
+                       if (n->asScriptInset() && n->asScriptInset()->hasDown()) {
+                               pushLeft(n);
+                               idx() = 0;
+                               pos() = 0;
+                               return true;
+                       }
                }
        }
 
@@ -572,12 +629,14 @@ bool MathCursor::down(bool sel)
 
 bool MathCursor::toggleLimits()
 {
-       MathScriptInset * p = prevScriptInset();
-       if (!p)
+       if (!hasPrevAtom())
                return false;
-       int old = p->limits();
-       p->limits(old < 0 ? 1 : -1);
-       return old != p->limits();
+       MathScriptInset * t = prevAtom()->asScriptInset();
+       if (!t)
+               return false;
+       int old = t->limits();
+       t->limits(old < 0 ? 1 : -1);
+       return old != t->limits();
 }
 
 
@@ -591,23 +650,30 @@ void MathCursor::macroModeClose()
 {
        string s = macroName();
        if (s.size()) {
-               pos() = pos() - s.size();
-               for (unsigned i = 0; i < s.size(); ++i)
-                       plainErase();
-               lastcode_ = LM_TC_VAR;
-               interpret("\\" + s);
+               size_type old = pos();
+               pos() -= s.size();
+               array().erase(pos(), old);
+               interpret(s);
        }
 }
 
 
+int MathCursor::macroNamePos() const
+{
+       for (int i = pos() - 1; i >= 0; --i) { 
+               MathAtom & p = array().at(i);
+               if (p->code() == LM_TC_TEX && p->getChar() == '\\')
+                       return i;
+       }
+       return -1;
+}
+
+
 string MathCursor::macroName() const
 {
        string s;
-       int p = pos() - 1;
-       while (p >= 0 && array().nextInset(p)->code() == LM_TC_TEX) {
-               s = array().nextInset(p)->getChar() + s;
-               --p;
-       }
+       for (int i = macroNamePos(); i >= 0 && i < int(pos()); ++i) 
+               s += array().at(i)->getChar();
        return s;
 }
 
@@ -649,7 +715,8 @@ void MathCursor::selPaste()
 {
        seldump("selPaste");
        theSelection.paste(*this);
-       selClear();
+       theSelection.grab(*this);
+       //selClear();
 }
 
 
@@ -702,7 +769,8 @@ void MathCursor::drawSelection(Painter & pain) const
                int y2 = c.yo() + c.descent();
                pain.fillRectangle(x1, y1, x2 - x1, y2 - y1, LColor::selection);
        } else {
-               std::vector<int> indices = i1.par_->idxBetween(i1.idx_, i2.idx_);
+               std::vector<MathInset::idx_type> indices
+                       = (*i1.par_)->idxBetween(i1.idx_, i2.idx_);
                for (unsigned i = 0; i < indices.size(); ++i) {
                        MathXArray & c = i1.xcell(indices[i]);
                        int x1 = c.xo();
@@ -715,13 +783,6 @@ void MathCursor::drawSelection(Painter & pain) const
 }
 
 
-MathTextCodes MathCursor::nextCode() const
-{
-       //return (pos() == size()) ? LM_TC_VAR : nextInset()->code();
-       return LM_TC_VAR;
-}
-
-
 void MathCursor::handleFont(MathTextCodes t)
 {
        macroModeClose();
@@ -731,15 +792,15 @@ void MathCursor::handleFont(MathTextCodes t)
                getSelection(i1, i2); 
                if (i1.idx_ == i2.idx_) {
                        MathArray & ar = i1.cell();
-                       for (int pos = i1.pos_; pos != i2.pos_; ++pos) 
-                               ar.nextInset(pos)->handleFont(t);
+                       for (MathInset::pos_type pos = i1.pos_; pos != i2.pos_; ++pos)
+                               ar.at(pos)->handleFont(t);
                }
        } else 
                lastcode_ = (lastcode_ == t) ? LM_TC_VAR : t;
 }
 
 
-void MathCursor::handleDelim(latexkeys const * l, latexkeys const * r)
+void MathCursor::handleDelim(string const & l, string const & r)
 {
        handleNest(new MathDelimInset(l, r));
 }
@@ -751,8 +812,8 @@ void MathCursor::handleNest(MathInset * p)
                selCut();
                p->cell(0) = theSelection.glue();
        }
-       insert(p);
-       pushRight(p);
+       insert(MathAtom(p)); // this invalidates p!
+       pushRight(prevAtom());
 }
 
 
@@ -766,9 +827,9 @@ void MathCursor::getPos(int & x, int & y)
 }
 
 
-MathInset * MathCursor::par() const
+MathAtom & MathCursor::par() const
 {
-       return cursor().par_;
+       return *cursor().par_;
 }
 
 
@@ -778,25 +839,25 @@ InsetFormulaBase const * MathCursor::formula()
 }
 
 
-int MathCursor::idx() const
+MathCursor::idx_type MathCursor::idx() const
 {
        return cursor().idx_;
 }
 
 
-int & MathCursor::idx()
+MathCursor::idx_type & MathCursor::idx()
 {
        return cursor().idx_;
 }
 
 
-int MathCursor::pos() const
+MathCursor::pos_type MathCursor::pos() const
 {
        return cursor().pos_;
 }
 
 
-int & MathCursor::pos()
+MathCursor::pos_type & MathCursor::pos()
 {
        return cursor().pos_;
 }
@@ -804,7 +865,7 @@ int & MathCursor::pos()
 
 bool MathCursor::inMacroMode() const
 {
-       return lastcode_ == LM_TC_TEX;
+       return macroNamePos() != -1;
 }
 
 
@@ -814,12 +875,13 @@ bool MathCursor::selection() const
 }
 
 
-MathArrayInset * MathCursor::enclosingArray(int & idx) const
+MathArrayInset * MathCursor::enclosingArray(MathCursor::idx_type & idx) const
 {
        for (int i = Cursor_.size() - 1; i >= 0; --i) {
-               if (Cursor_[i].par_->isArray()) {
+               MathArrayInset * p = (*Cursor_[i].par_)->asArrayInset();
+               if (p) {
                        idx = Cursor_[i].idx_;
-                       return static_cast<MathArrayInset *>(Cursor_[i].par_);
+                       return p;
                }
        }
        return 0;
@@ -828,9 +890,22 @@ MathArrayInset * MathCursor::enclosingArray(int & idx) const
 
 void MathCursor::pullArg(bool goright)
 {
-       // pullArg
        dump("pullarg");
        MathArray a = array();
+
+       MathScriptInset const * p = par()->asScriptInset();
+       if (p) {
+               // special handling for scripts
+               const bool up = p->hasUp();
+               popLeft();
+               MathScriptInset * q = nextAtom()->asScriptInset();
+               if (q)
+                       q->removeScript(up);
+               ++pos();
+               array().insert(pos(), a);
+               return;
+       }
+
        if (popLeft()) {
                plainErase();
                array().insert(pos(), a);
@@ -853,106 +928,85 @@ void MathCursor::normalize() const
 #endif
        MathCursor * it = const_cast<MathCursor *>(this);
 
-       if (idx() < 0)
-               lyxerr << "this should not really happen - 1: " << idx() << "\n";
        if (idx() >= par()->nargs()) {
-               lyxerr << "this should not really happen - 2: "
+               lyxerr << "this should not really happen - 1: "
                       << idx() << " " << par()->nargs() << "\n";
                dump("error 2");
        }
-       it->idx()    = max(idx(), 0);
        it->idx()    = min(idx(), par()->nargs() - 1);
 
-       if (pos() < 0)
-               lyxerr << "this should not really happen - 3: " << pos() << "\n";
        if (pos() > size()) {
-               lyxerr << "this should not really happen - 4: "
+               lyxerr << "this should not really happen - 2: "
                       << pos() << " " << size() << "\n";
                dump("error 4");
        }
-       it->pos() = max(pos(), 0);
        it->pos() = min(pos(), size());
 }
 
 
-int MathCursor::size() const
+MathCursor::size_type MathCursor::size() const
 {
        return array().size();
 }
 
 
-int MathCursor::col() const
+MathCursor::col_type MathCursor::col() const
 {
        return par()->col(idx());
 }
 
 
-int MathCursor::row() const
+MathCursor::row_type MathCursor::row() const
 {
        return par()->row(idx());
 }
 
 
-/*
-char MathCursorPos::getChar() const
+bool MathCursor::hasPrevAtom() const
 {
-       return array().getChar(pos());
+       return pos() > 0;
 }
 
 
-string MathCursorPos::readString()
+bool MathCursor::hasNextAtom() const
 {
-       string s;
-       int code = nextCode();
-       for ( ; OK() && nextCode() == code; Next()) 
-               s += getChar();
-
-       return s;
+       return pos() < size();
 }
-*/
 
 
-MathInset * MathCursor::prevInset() const
+MathAtom const & MathCursor::prevAtom() const
 {
-       normalize();
-       if (!pos())
-               return 0;
-       return array().nextInset(pos() - 1);
+       lyx::Assert(pos() > 0);
+       return array().at(pos() - 1);
 }
 
 
-MathInset * MathCursor::nextInset() const
+MathAtom & MathCursor::prevAtom()
 {
-       normalize();
-       return array().nextInset(pos());
+       lyx::Assert(pos() > 0);
+       return array().at(pos() - 1);
 }
 
 
-MathScriptInset * MathCursor::prevScriptInset() const
+MathAtom const & MathCursor::nextAtom() const
 {
-       normalize();
-       MathInset * p = prevInset();
-       return (p && p->isScriptInset()) ? static_cast<MathScriptInset *>(p) : 0;
+       lyx::Assert(pos() < size());
+       return array().at(pos());
 }
 
 
-MathSpaceInset * MathCursor::prevSpaceInset() const
+MathAtom & MathCursor::nextAtom()
 {
-       normalize();
-       MathInset * p = prevInset();
-       return (p && p->isSpaceInset()) ? static_cast<MathSpaceInset *>(p) : 0;
+       lyx::Assert(pos() < size());
+       return array().at(pos());
 }
 
 
 MathArray & MathCursor::array() const
 {
        static MathArray dummy;
-       if (!par()) {
-               lyxerr << "############  par_ not valid\n";
-               return dummy;
-       }
 
-       if (idx() < 0 || idx() >= par()->nargs()) {
+       if (idx() >= par()->nargs()) {
                lyxerr << "############  idx_ " << idx() << " not valid\n";
                return dummy;
        }
@@ -998,7 +1052,10 @@ void MathCursor::breakLine()
        while (popRight())
                ;
 
-       MathMatrixInset * p = outerPar();
+       MathMatrixInset * p = formula()->par()->asMatrixInset();
+       if (!p)
+               return;
+
        if (p->getType() == LM_OT_SIMPLE || p->getType() == LM_OT_EQUATION) {
                p->mutate(LM_OT_EQNARRAY);
                idx() = 0;
@@ -1007,10 +1064,10 @@ void MathCursor::breakLine()
                p->addRow(row());
 
                // split line
-               const int r = row();
-               for (int c = col() + 1; c < p->ncols(); ++c) {
-                       const int i1 = p->index(r, c);
-                       const int i2 = p->index(r + 1, c);      
+               const row_type r = row();
+               for (col_type c = col() + 1; c < p->ncols(); ++c) {
+                       const MathMatrixInset::idx_type i1 = p->index(r, c);
+                       const MathMatrixInset::idx_type i2 = p->index(r + 1, c);        
                        lyxerr << "swapping cells " << i1 << " and " << i2 << "\n";
                        p->cell(i1).swap(p->cell(i2));
                }
@@ -1024,17 +1081,17 @@ void MathCursor::breakLine()
 
 char MathCursor::valign() const
 {
-       int idx;
+       idx_type idx;
        MathArrayInset * p = enclosingArray(idx);
-       return p ? p->valign() : 0;
+       return p ? p->valign() : '\0';
 }
 
 
 char MathCursor::halign() const
 {
-       int idx;
+       idx_type idx;
        MathArrayInset * p = enclosingArray(idx);
-       return p ? p->halign(idx % p->ncols()) : 0;
+       return p ? p->halign(idx % p->ncols()) : '\0';
 }
 
 
@@ -1100,13 +1157,24 @@ bool MathCursor::goUp()
        if (par()->idxUp(idx(), pos()))
                return true;
 
+       // leave subscript to the nearest side  
+       MathScriptInset * p = par()->asScriptInset();
+       if (p && p->hasDown()) {
+               if (pos() <= size() / 2)
+                       popLeft();
+               else
+                       popRight();             
+               return true;
+       }
+
        // if not, apply brute force.
        int x0;
        int y0;
        getPos(x0, y0);
        std::vector<MathCursorPos> save = Cursor_;
+       MathAtom const & out = formula()->par();
        y0 -= xarray().ascent();
-       for (int y = y0 - 4; y > outerPar()->yo() - outerPar()->ascent(); y -= 4) {
+       for (int y = y0 - 4; y > out->yo() - out->ascent(); y -= 4) {
                setPos(x0, y);
                if (save != Cursor_ && xarray().yo() < y0)
                        return true;    
@@ -1122,13 +1190,24 @@ bool MathCursor::goDown()
        if (par()->idxDown(idx(), pos()))
                return true;
 
+       // leave superscript to the nearest side        
+       MathScriptInset * p = par()->asScriptInset();
+       if (p && p->hasUp()) {
+               if (pos() <= size() / 2)
+                       popLeft();
+               else
+                       popRight();             
+               return true;
+       }
+
        // if not, apply brute force.
        int x0;
        int y0;
        getPos(x0, y0);
        std::vector<MathCursorPos> save = Cursor_;
+       MathAtom const & out = formula()->par();
        y0 += xarray().descent();
-       for (int y = y0 + 4; y < outerPar()->yo() + outerPar()->descent(); y += 4) {
+       for (int y = y0 + 4; y < out->yo() + out->descent(); y += 4) {
                setPos(x0, y);
                if (save != Cursor_ && xarray().yo() > y0)
                        return true;    
@@ -1150,162 +1229,123 @@ bool MathCursor::idxRight()
 }
 
 
-MathMatrixInset * MathCursor::outerPar() const
-{
-       return
-               static_cast<MathMatrixInset *>(const_cast<MathInset *>(formula_->par()));
-}
-
-
 void MathCursor::interpret(string const & s)
 {
-       //lyxerr << "interpret: '" << s << "'\n";
+       //lyxerr << "interpret 1: '" << s << "'\n";
        //lyxerr << "in: " << in_word_set(s) << " \n";
 
        if (s.empty())
                return;
 
-       char c = s[0];
+       if (s.size() == 1) {
+               interpret(s[0]);
+               return;
+       }
 
-       //lyxerr << "char: '" << c << "'  int: " << int(c) << endl;
-       //owner_->getIntl()->getTrans().TranslateAndInsert(c, lt);      
-       //lyxerr << "trans: '" << c << "'  int: " << int(c) << endl;
+       //lyxerr << "char: '" << s[0] << "'  int: " << int(s[0]) << endl;
+       //owner_->getIntl()->getTrans().TranslateAndInsert(s[0], lt);   
+       //lyxerr << "trans: '" << s[0] << "'  int: " << int(s[0]) << endl;
 
-       if (s.size() > 8 && s.substr(0, 8) == "\\matrix ") {
-               int m = 1;
-               int n = 1;
+       if (s.size() > 7 && s.substr(0, 7) == "matrix ") {
+               unsigned int m = 1;
+               unsigned int n = 1;
                string v_align;
                string h_align;
-               istringstream is(s.substr(8).c_str());
+               istringstream is(s.substr(7).c_str());
                is >> m >> n >> v_align >> h_align;
-               m = std::max(1, m);
-               n = std::max(1, n);
+               m = std::max(1u, m);
+               n = std::max(1u, n);
                v_align += 'c';
-               MathArrayInset * p = new MathArrayInset(m, n);
-               p->valign(v_align[0]);
-               p->halign(h_align);
-               niceInsert(p);
+               niceInsert(MathAtom(new MathArrayInset(m, n, v_align[0], h_align)));
                return;
        }
 
-       if (s == "\\over" || s == "\\choose") {
+       if (s == "\\over" || s == "\\choose" || s == "\\atop") {
                MathArray ar = array();
-               MathInset * p = createMathInset(in_word_set(s.substr(1)));
-               p->cell(0).swap(array());
+               MathAtom t = createMathInset(s.substr(1));
+               t->asNestInset()->cell(0).swap(array());
                pos() = 0;
-               niceInsert(p);
+               niceInsert(t);
                popRight();
                left();
                return;
        }
 
-       if (s.size() > 1) {
-               niceInsert(createMathInset(s.substr(1)));
-               return;
-       }
+       niceInsert(createMathInset(s.substr(1)));
+}
 
 
-       // we got just a single char now
+void MathCursor::interpret(char c)
+{
+       //lyxerr << "interpret 2: '" << c << "'\n";
 
-       if (c == '^' || c == '_') {
-               bool const up = (s[0] == '^');
-               selCut();       
-               MathScriptInset * p = prevScriptInset();
-               if (!p) {
-                       MathInset * b = prevInset();
-                       if (b && b->isScriptable()) {
-                               p = new MathScriptInset(up, !up, b->clone());
-                               posLeft();
-                               plainErase();
-                       } else 
-                               p = new MathScriptInset(up, !up);
-                       insert(p);
+       if (inMacroMode()) {
+               string name = macroName();
+
+               if (name == "\\" && c == '#') {
+                       insert(c, LM_TC_TEX);
+                       return;
                }
-               pushRight(p);
-               if (up)
-                       p->up(true);
-               else
-                       p->down(true);
-               idx() = up ? 0 : 1;
-               pos() = 0;
-               selPaste();
-               return;
-       }
 
-       if (c == '{') {
-               niceInsert(new MathScopeInset);
-               return;
-       }
+               if (name == "\\" && c == '\\') {
+                       backspace();
+                       interpret("\\backslash");
+                       return;
+               }
 
-       if (isalpha(c) && (lastcode_ == LM_TC_GREEK || lastcode_ == LM_TC_GREEK1)) {
-               static char const greek[26] =
-                       {'A', 'B', 'X',  0 , 'E',  0 ,  0 , 'H', 'I',  0 ,
-                        'K',  0 , 'M', 'N', 'O',  0 ,  0 , 'P',  0 , 'T',
-                        0,  0,   0,   0,   0 , 'Z' };
-                       
-               MathTextCodes code = LM_TC_SYMB;
-               if ('A' <= c && c <= 'Z' && greek[c - 'A']) {
-                       code = LM_TC_RM;
-                       c = greek[c - 'A'];
+               if (name == "\\#" && '1' <= c && c <= '9') {
+                       insert(c, LM_TC_TEX);
+                       macroModeClose();
+                       return;
                }
-               insert(c, code);
-       
-#warning greek insert problem? look here!
-               //if (lastcode_ == LM_TC_GREEK1)
-                       lastcode_ = LM_TC_VAR;
-               return; 
-       }
 
-       if (selection_)
-               selDel();
+               if (isalpha(c)) {
+                       insert(c, LM_TC_TEX);
+                       return;
+               }
 
-       if (lastcode_ == LM_TC_TEX) {
-               if (macroName().empty()) {
+               if (name == "\\") {
                        insert(c, LM_TC_TEX);
-                       if (!isalpha(c)) {
-                               macroModeClose();
-                               lastcode_ = LM_TC_VAR;
-                       }
-               } else {
-                       if (isalpha(c))
-                               insert(c, LM_TC_TEX);
-                       else {
-                               macroModeClose();
-                               lastcode_ = LM_TC_VAR;
-                       }
+                       macroModeClose();
+                       return;
                }
+
+               macroModeClose();
                return;
        }
 
-       if (strchr("0123456789;:!|[]().,?+/-*<>=", c)) {
-               if (lastcode_ != LM_TC_TEXTRM)
-                       lastcode_ = LM_TC_CONST;
-               insert(c, lastcode_);
+       // no macro mode
+       if (c == '^' || c == '_') {
+               const bool up = (c == '^');
+               selCut();
+               if (hasPrevAtom() && prevAtom()->asScriptInset()) {
+                       prevAtom()->asScriptInset()->ensure(up);
+                       pushRight(prevAtom());
+                       pos() = size();
+               } else if (hasNextAtom() && nextAtom()->asScriptInset()) {
+                       nextAtom()->asScriptInset()->ensure(up);
+                       pushLeft(nextAtom());
+                       pos() = 0;
+               } else {
+                       plainInsert(MathAtom(new MathScriptInset(up)));
+                       pushRight(prevAtom());
+               }
+               idx() = up;
+               selPaste();
                return;
        }
 
-       if (strchr("#$%{|}", c)) {
-               if (lastcode_ != LM_TC_TEXTRM)
-                       lastcode_ = LM_TC_SPECIAL;
-               insert(c, lastcode_);
+       if (selection_)
+               selDel();
+
+       if (lastcode_ == LM_TC_TEXTRM) {
+               insert(c, LM_TC_TEXTRM);
                return;
        }
 
        if (c == ' ') {
-               if (inMacroMode()) {
-                       macroModeClose();
-                       lastcode_ = LM_TC_VAR;
-                       return;
-               }
-
-               MathSpaceInset * p = prevSpaceInset();
-               if (p) {
-                       p->incSpace();
-                       return;
-               }
-
-               if (lastcode_ == LM_TC_TEXTRM) {
-                       insert(c, LM_TC_TEXTRM);
+               if (hasPrevAtom() && prevAtom()->asSpaceInset()) {
+                       prevAtom()->asSpaceInset()->incSpace();
                        return;
                }
 
@@ -1319,22 +1359,54 @@ void MathCursor::interpret(string const & s)
                return;
        }
 
-       if (c == '\'' || c == '@') {
-               insert(c, LM_TC_VAR);
+       if (strchr("{}", c)) {
+               insert(c, LM_TC_TEX);
                return;
        }
 
-       if (c == '\\') {
-               lastcode_ = LM_TC_TEX;
-               //bv->owner()->message(_("TeX mode"));
+       if (strchr("#$%", c)) {
+               insert(MathAtom(new MathSpecialCharInset(c)));  
+               lastcode_ = LM_TC_VAR;
+               return;
+       }
+
+       if (isalpha(c) && (lastcode_ == LM_TC_GREEK || lastcode_ == LM_TC_GREEK1)) {
+               static char const greekl[][26] =
+                       {"alpha", "beta", "chi", "delta", "epsilon", "phi",
+                        "gamma", "eta", "iota", "epsilon", "kappa", "lambda", "mu",
+                        "nu", "omikron", "pi", "vartheta", "rho", "sigma",
+                        "tau", "upsilon", "theta", "omega", "xi", "varphi", "zeta"};
+               static char const greeku[][26] =
+                       {"Alpha", "Beta", "chi", "Delta", "varepsilon", "Phi",
+                        "Gamma", "Eta", "Iota", "Epsilon", "Kappa", "Lambda", "Mu",
+                        "Nu", "Omikron", "Pi", "vartheta", "varrho", "Sigma", "varsigma",
+                        "Upsilon", "Theta", "Omega", "Xi", "Varphi", "Zeta"};
+       
+               latexkeys const * l = 0;        
+               if ('a' <= c && c <= 'z')
+                       l = in_word_set(greekl[c - 'a']);
+               if ('A' <= c && c <= 'Z')
+                       l = in_word_set(greeku[c - 'A']);
+       
+               if (l)
+                       insert(createMathInset(l));
+               else
+                       insert(c, LM_TC_VAR);
+
+#warning greek insert problem? look here!
+               if (lastcode_ == LM_TC_GREEK1)
+                       lastcode_ = LM_TC_VAR;
                return; 
        }
 
-       if (isalpha(c)) {
-               insert(c, lastcode_);
+       if (c == '\\') {
+               insert(c, LM_TC_TEX);
+               //bv->owner()->message(_("TeX mode"));
                return; 
        }
 
+       // no special circumstances, so insert the character without any fuss
+       insert(c, LM_TC_MIN);
 }
 
 
@@ -1360,27 +1432,27 @@ bool operator<(MathCursorPos const & ti, MathCursorPos const & it)
 }
 
 
-MathArray & MathCursorPos::cell(int idx) const
+MathArray & MathCursorPos::cell(MathCursor::idx_type idx) const
 {
-       return par_->cell(idx);
+       return (*par_)->cell(idx);
 }
 
 
 MathArray & MathCursorPos::cell() const
 {
-       return par_->cell(idx_);
+       return (*par_)->cell(idx_);
 }
 
 
-MathXArray & MathCursorPos::xcell(int idx) const
+MathXArray & MathCursorPos::xcell(MathCursor::idx_type idx) const
 {
-       return par_->xcell(idx);
+       return (*par_)->xcell(idx);
 }
 
 
 MathXArray & MathCursorPos::xcell() const
 {
-       return par_->xcell(idx_);
+       return (*par_)->xcell(idx_);
 }
 
 
@@ -1395,3 +1467,4 @@ MathCursorPos MathCursor::normalAnchor() const
        return normal;
 }
 
+