From: Richard Heck <rgheck@comcast.net>
Date: Thu, 31 Dec 2009 03:50:12 +0000 (+0000)
Subject: Introduce a return value for mathmlize(). We will need this to be able
X-Git-Tag: 2.0.0~4669
X-Git-Url: https://git.lyx.org/gitweb/?a=commitdiff_plain;h=8a0134cc8ce7de41d6d6911a1c4219ca958f2b71;p=features.git

Introduce a return value for mathmlize(). We will need this to be able
to defer labels.


git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@32684 a592a061-630c-0410-9148-cb99ea01b6c8
---

diff --git a/development/HTML/HTML.notes b/development/HTML/HTML.notes
index 9c80dbae46..b9750e3043 100644
--- a/development/HTML/HTML.notes
+++ b/development/HTML/HTML.notes
@@ -52,37 +52,36 @@ These insets work but still need work:
 Math
   We have a fair bit of math now working via MathML output, but there are still some 
   isues, and not all the insets work. Here are the ones I know still need work:
-	  - AMSArray
-    - Array
-    - Big: Not sure if we can actually do anything here. Probably they should
-      just be treated as delimiters.
-    - BoldSymbol: Should be easy.
-    - Box
-    - Cases
-    - Diff: Code exists, but I do not know if it is right.
-    - Font
-    - Binom (in Frac): None of these tags exist in MathML 2.0. We'll
-      just output a fraction with delimiters.
-    - Lefteqn
-    - MBox: Use <mtext>.
-    - Overset: Use <mover>.
-    - Par?
-    - Phantom: There is some support for this in MathML....
-    - Ref: Probably needs to be deferred somehow, which is a hassle, because it
-      means the whole MathML output business needs a new argument.
-    - Size: Unclear if we want to do anything here, though we could. See
-      lib/symbols for the commands supported, of course.
-    - Space: Needs checking.
-    - SpecialChar: Needs checking.
-    - Split
-    - Stackrel: Use <mover>, probably.
-    - Substack: This is a stack of however many cells, all in a smaller style.
-      Probably do something with <mover>, again.
-    - Tabular: This is more or less a text-like table in math. Probably output it
-      as a table, but set the font.
-    - Underset: Use <munder>.
-    - XArrow: Contents above and below an arrow. Use...?
-    - XYMatrix: Not sure how this differs from ordinary ones.
+	- AMSArray
+	- Array
+	- Big: Not sure if we can actually do anything here. Probably they should
+		just be treated as delimiters.
+	- BoldSymbol: Should be easy.
+	- Box
+	- Cases
+	- Diff: Code exists, but I do not know if it is right.
+	- Font
+	- Binom (in Frac): None of these tags exist in MathML 2.0. We'll
+		just output a fraction with delimiters.
+	- Lefteqn
+	- MBox: Use <mtext>.
+	- Overset: Use <mover>.
+	- Par?
+	- Phantom: There is some support for this in MathML....
+	- Ref: Needs to be deferred.
+	- Size: Unclear if we want to do anything here, though we could. See
+		lib/symbols for the commands supported, of course.
+	- Space: Needs checking.
+	- SpecialChar: Needs checking.
+	- Split
+	- Stackrel: Use <mover>, probably.
+	- Substack: This is a stack of however many cells, all in a smaller style.
+		Probably do something with <mover>, again.
+	- Tabular: This is more or less a text-like table in math. Probably output it
+		as a table, but set the font.
+	- Underset: Use <munder>.
+	- XArrow: Contents above and below an arrow. Use...?
+	- XYMatrix: Not sure how this differs from ordinary ones.
 
 
 These insets do not work and are not yet scheduled to work:
diff --git a/src/mathed/InsetMath.cpp b/src/mathed/InsetMath.cpp
index 0a9772c676..a5cd28a284 100644
--- a/src/mathed/InsetMath.cpp
+++ b/src/mathed/InsetMath.cpp
@@ -120,12 +120,13 @@ void InsetMath::mathematica(MathematicaStream & os) const
 }
 
 
-void InsetMath::mathmlize(MathStream & os) const
+docstring InsetMath::mathmlize(MathStream & os) const
 {
 	os << MTag("mi");
 	NormalStream ns(os.os());
 	normalize(ns);
 	os << ETag("mi");
+	return docstring();
 }
 
 
diff --git a/src/mathed/InsetMath.h b/src/mathed/InsetMath.h
index 555762c8c7..12ea7ab06c 100644
--- a/src/mathed/InsetMath.h
+++ b/src/mathed/InsetMath.h
@@ -187,7 +187,7 @@ public:
 	/// write content as something readable by Mathematica
 	virtual void mathematica(MathematicaStream &) const;
 	/// write content as something resembling MathML
-	virtual void mathmlize(MathStream &) const;
+	virtual docstring mathmlize(MathStream &) const;
 	/// write content as something readable by Octave
 	virtual void octave(OctaveStream &) const;
 
diff --git a/src/mathed/InsetMathBox.cpp b/src/mathed/InsetMathBox.cpp
index d432794fc0..701a0bb634 100644
--- a/src/mathed/InsetMathBox.cpp
+++ b/src/mathed/InsetMathBox.cpp
@@ -52,7 +52,7 @@ void InsetMathBox::normalize(NormalStream & os) const
 }
 
 
-void InsetMathBox::mathmlize(MathStream & ms) const
+docstring InsetMathBox::mathmlize(MathStream & ms) const
 {	
 	// FIXME This doesn't actually work yet. We need to be able to signal 
 	// that we are in text mode and then just call ms << cell(0). So we
@@ -60,6 +60,7 @@ void InsetMathBox::mathmlize(MathStream & ms) const
 	ms << MTag("mtext");
 	ms.os() << cell(0);
 	ms << ETag("mtext");
+	return docstring();
 }
 
 
diff --git a/src/mathed/InsetMathBox.h b/src/mathed/InsetMathBox.h
index 4ef299401d..03d2da9f9e 100644
--- a/src/mathed/InsetMathBox.h
+++ b/src/mathed/InsetMathBox.h
@@ -35,7 +35,7 @@ public:
 	///
 	void normalize(NormalStream & ns) const;
 	///
-	void mathmlize(MathStream & ms) const;
+	docstring mathmlize(MathStream & ms) const;
 	///
 	void infoize(odocstream & os) const;
 	///
@@ -66,7 +66,7 @@ public:
 	/// write normalized content
 	void normalize(NormalStream & ns) const;
 	///
-	//void mathmlize(MathStream & ms) const;
+	//docstring mathmlize(MathStream & ms) const;
 	///
 	void infoize(odocstream & os) const;
 private:
@@ -89,7 +89,7 @@ public:
 	/// write normalized content
 	void normalize(NormalStream & ns) const;
 	///
-	//void mathmlize(MathStream & ms) const;
+	//docstring mathmlize(MathStream & ms) const;
 	///
 	mode_type currentMode() const { return TEXT_MODE; }
 	///
@@ -116,7 +116,7 @@ public:
 	///
 	void write(WriteStream & os) const;
 	///
-	//void mathmlize(MathStream & ms) const;
+	//docstring mathmlize(MathStream & ms) const;
 	/// write normalized content
 	void normalize(NormalStream & ns) const;
 	///
diff --git a/src/mathed/InsetMathBrace.cpp b/src/mathed/InsetMathBrace.cpp
index c1034c9aee..4bf24dfb81 100644
--- a/src/mathed/InsetMathBrace.cpp
+++ b/src/mathed/InsetMathBrace.cpp
@@ -13,6 +13,7 @@
 #include "InsetMathBrace.h"
 
 #include "MathData.h"
+#include "MathExtern.h"
 #include "MathStream.h"
 #include "MathSupport.h"
 #include "MetricsInfo.h"
@@ -94,9 +95,12 @@ void InsetMathBrace::octave(OctaveStream & os) const
 }
 
 
-void InsetMathBrace::mathmlize(MathStream & os) const
+docstring InsetMathBrace::mathmlize(MathStream & os) const
 {
-	os << MTag("mrow") << cell(0) << ETag("mrow");
+	os << MTag("mrow");
+	docstring const rv = lyx::mathmlize(cell(0), os);
+	os << ETag("mrow");
+	return rv;
 }
 
 
diff --git a/src/mathed/InsetMathBrace.h b/src/mathed/InsetMathBrace.h
index e8e3ea9557..6af0ca32b0 100644
--- a/src/mathed/InsetMathBrace.h
+++ b/src/mathed/InsetMathBrace.h
@@ -46,7 +46,7 @@ public:
 	///
 	void octave(OctaveStream &) const;
 	///
-	void mathmlize(MathStream &) const;
+	docstring mathmlize(MathStream &) const;
 	///
 	void infoize(odocstream & os) const;
 	///
diff --git a/src/mathed/InsetMathChar.cpp b/src/mathed/InsetMathChar.cpp
index 8e02c6a92c..27093e8504 100644
--- a/src/mathed/InsetMathChar.cpp
+++ b/src/mathed/InsetMathChar.cpp
@@ -165,12 +165,12 @@ void InsetMathChar::octave(OctaveStream & os) const
 // mathalpha, then we'll treat it as an identifier, otherwise as an 
 // operator.
 // Worst case: We get bad spacing, or bad italics.
-void InsetMathChar::mathmlize(MathStream & ms) const
+docstring InsetMathChar::mathmlize(MathStream & ms) const
 {
 	switch (char_) {
-		case '<': ms << "<mo>&lt;</mo>"; return;
-		case '>': ms << "<mo>&gt;</mo>"; return;
-		case '&': ms << "<mo>&amp;</mo>"; return;
+		case '<': ms << "<mo>&lt;</mo>"; return docstring();
+		case '>': ms << "<mo>&gt;</mo>"; return docstring();
+		case '&': ms << "<mo>&amp;</mo>"; return docstring();
 		default: break;
 	}
 	
@@ -179,6 +179,7 @@ void InsetMathChar::mathmlize(MathStream & ms) const
 			? "mi" : "mo";
 	// we don't use MTag and ETag because we do not want the spacing
 	ms << "<" << type << ">" << char(char_) << "</" << type << ">";	
+	return docstring();
 }
 
 
diff --git a/src/mathed/InsetMathChar.h b/src/mathed/InsetMathChar.h
index 6dba328c4e..d1a865fc15 100644
--- a/src/mathed/InsetMathChar.h
+++ b/src/mathed/InsetMathChar.h
@@ -41,7 +41,7 @@ public:
 	///
 	void octave(OctaveStream & os) const;
 	///
-	void mathmlize(MathStream & ms) const;
+	docstring mathmlize(MathStream & ms) const;
 	/// identifies Charinsets
 	InsetMathChar const * asCharInset() const { return this; }
 	///
diff --git a/src/mathed/InsetMathComment.cpp b/src/mathed/InsetMathComment.cpp
index ebfba7a859..92693a2c7e 100644
--- a/src/mathed/InsetMathComment.cpp
+++ b/src/mathed/InsetMathComment.cpp
@@ -86,9 +86,10 @@ void InsetMathComment::octave(OctaveStream &) const
 {}
 
 
-void InsetMathComment::mathmlize(MathStream & os) const
+docstring InsetMathComment::mathmlize(MathStream & os) const
 {
 	os << MTag("comment") << cell(0) << cell(1) << ETag("comment");
+	return docstring();
 }
 
 
diff --git a/src/mathed/InsetMathComment.h b/src/mathed/InsetMathComment.h
index bb775a74cb..2ab35c2805 100644
--- a/src/mathed/InsetMathComment.h
+++ b/src/mathed/InsetMathComment.h
@@ -44,7 +44,7 @@ public:
 	///
 	void octave(OctaveStream &) const;
 	///
-	void mathmlize(MathStream &) const;
+	docstring mathmlize(MathStream &) const;
 	///
 	void infoize(odocstream & os) const;
 	///
diff --git a/src/mathed/InsetMathDecoration.cpp b/src/mathed/InsetMathDecoration.cpp
index 629a440abf..825b212c9d 100644
--- a/src/mathed/InsetMathDecoration.cpp
+++ b/src/mathed/InsetMathDecoration.cpp
@@ -14,6 +14,7 @@
 #include "InsetMathDecoration.h"
 
 #include "MathData.h"
+#include "MathExtern.h"
 #include "MathParser.h"
 #include "MathSupport.h"
 #include "MathStream.h"
@@ -205,16 +206,18 @@ namespace {
 	}
 }
 
-void InsetMathDecoration::mathmlize(MathStream & os) const
+docstring InsetMathDecoration::mathmlize(MathStream & os) const
 {
 	Translator const & t = translator();
 	Translator::const_iterator cur = t.find(to_utf8(key_->name));
-	LASSERT(cur != t.end(), return);
+	LASSERT(cur != t.end(), return docstring());
 	char const * const outag = cur->second.over ? "mover" : "munder";
-	os << MTag(outag)
-		 << MTag("mrow") << cell(0) << ETag("mrow")
+	os << MTag(outag) << MTag("mrow");
+	docstring const rv = lyx::mathmlize(cell(0), os);
+	os << ETag("mrow")
 		 << from_ascii("<mo stretchy=\"true\">" + cur->second.tag + "</mo>")
 		 << ETag(outag);
+	return rv;
 }
 
 
diff --git a/src/mathed/InsetMathDecoration.h b/src/mathed/InsetMathDecoration.h
index 22c9f9bed3..7d77b49ae3 100644
--- a/src/mathed/InsetMathDecoration.h
+++ b/src/mathed/InsetMathDecoration.h
@@ -42,7 +42,7 @@ public:
 	///
 	InsetCode lyxCode() const { return MATH_DECORATION_CODE; }
 	///
-	void mathmlize(MathStream &) const;
+	docstring mathmlize(MathStream &) const;
 
 private:
 	virtual Inset * clone() const;
diff --git a/src/mathed/InsetMathDelim.cpp b/src/mathed/InsetMathDelim.cpp
index 459866c924..6da49562eb 100644
--- a/src/mathed/InsetMathDelim.cpp
+++ b/src/mathed/InsetMathDelim.cpp
@@ -14,6 +14,7 @@
 #include "InsetMathDelim.h"
 
 #include "MathData.h"
+#include "MathExtern.h"
 #include "MathStream.h"
 #include "MathSupport.h"
 #include "MetricsInfo.h"
@@ -161,10 +162,12 @@ void InsetMathDelim::mathematica(MathematicaStream & os) const
 }
 
 
-void InsetMathDelim::mathmlize(MathStream & os) const
+docstring InsetMathDelim::mathmlize(MathStream & os) const
 {
-	os << "<mo form='prefix' fence='true' stretchy='true' symmetric='true'>" << left_ << "</mo>"
-		<< cell(0) << "<mo form='postfix' fence='true' stretchy='true' symmetric='true'>" << right_ << "</mo>";
+	os << "<mo form='prefix' fence='true' stretchy='true' symmetric='true'>" << left_ << "</mo>";
+	docstring const rv = lyx::mathmlize(cell(0),os);
+	os << "<mo form='postfix' fence='true' stretchy='true' symmetric='true'>" << right_ << "</mo>";
+	return rv;
 }
 
 
diff --git a/src/mathed/InsetMathDelim.h b/src/mathed/InsetMathDelim.h
index 67e1db0906..fb70f24927 100644
--- a/src/mathed/InsetMathDelim.h
+++ b/src/mathed/InsetMathDelim.h
@@ -56,7 +56,7 @@ public:
 	///
 	void mathematica(MathematicaStream &) const;
 	///
-	void mathmlize(MathStream &) const;
+	docstring mathmlize(MathStream &) const;
 	///
 	void octave(OctaveStream &) const;
 	///
diff --git a/src/mathed/InsetMathDiff.cpp b/src/mathed/InsetMathDiff.cpp
index 1e990d7ffb..f044ab8f15 100644
--- a/src/mathed/InsetMathDiff.cpp
+++ b/src/mathed/InsetMathDiff.cpp
@@ -12,6 +12,7 @@
 
 #include "InsetMathDiff.h"
 #include "MathData.h"
+#include "MathExtern.h"
 #include "MathStream.h"
 
 #include "support/debug.h"
@@ -95,15 +96,17 @@ void InsetMathDiff::mathematica(MathematicaStream & os) const
 }
 
 
-void InsetMathDiff::mathmlize(MathStream & os) const
+docstring InsetMathDiff::mathmlize(MathStream & os) const
 {
 	os << "diff(";
+	docstring rv;
 	for (idx_type idx = 0; idx < nargs(); ++idx) {
 		if (idx != 0)
 			os << ',';
-		os << cell(idx);
+		rv += lyx::mathmlize(cell(idx), os);
 	}
 	os << ')';
+	return rv;
 }
 
 
diff --git a/src/mathed/InsetMathDiff.h b/src/mathed/InsetMathDiff.h
index 6253168397..f9f1aba088 100644
--- a/src/mathed/InsetMathDiff.h
+++ b/src/mathed/InsetMathDiff.h
@@ -39,7 +39,7 @@ public:
 	///
 	void mathematica(MathematicaStream &) const;
 	///
-	void mathmlize(MathStream &) const;
+	docstring mathmlize(MathStream &) const;
 	///
 	void maxima(MaximaStream &) const;
 	///
diff --git a/src/mathed/InsetMathDots.cpp b/src/mathed/InsetMathDots.cpp
index 8ca2a1e469..d1b18fa9b4 100644
--- a/src/mathed/InsetMathDots.cpp
+++ b/src/mathed/InsetMathDots.cpp
@@ -85,7 +85,7 @@ void InsetMathDots::validate(LaTeXFeatures & features) const
 }
 
 
-void InsetMathDots::mathmlize(MathStream & os) const
+docstring InsetMathDots::mathmlize(MathStream & os) const
 {
 	// which symbols we support is decided by what is listed in
 	// lib/symbols as generating a dots inset
@@ -106,6 +106,7 @@ void InsetMathDots::mathmlize(MathStream & os) const
 	else
 		LASSERT(false, ent = "&hellip;");
 	os << MTag("mi") << from_ascii(ent) << ETag("mi");
+	return docstring();
 }
 
 } // namespace lyx
diff --git a/src/mathed/InsetMathDots.h b/src/mathed/InsetMathDots.h
index 4f2428712c..4ba13351e9 100644
--- a/src/mathed/InsetMathDots.h
+++ b/src/mathed/InsetMathDots.h
@@ -35,7 +35,7 @@ public:
 	///
 	InsetCode lyxCode() const { return MATH_DOTS_CODE; }
 	///
-	void mathmlize(MathStream & os) const;
+	docstring mathmlize(MathStream & os) const;
 protected:
 	/// cache for the thing's height
 	mutable int dh_;
diff --git a/src/mathed/InsetMathEnsureMath.cpp b/src/mathed/InsetMathEnsureMath.cpp
index 8f738a8dae..149bae7d2c 100644
--- a/src/mathed/InsetMathEnsureMath.cpp
+++ b/src/mathed/InsetMathEnsureMath.cpp
@@ -13,8 +13,9 @@
 
 #include "InsetMathEnsureMath.h"
 
-#include "MathStream.h"
+#include "MathExtern.h"
 #include "MathData.h"
+#include "MathStream.h"
 
 #include <ostream>
 
@@ -67,9 +68,9 @@ void InsetMathEnsureMath::write(WriteStream & os) const
 }
 
 
-void InsetMathEnsureMath::mathmlize(MathStream & os) const
+docstring InsetMathEnsureMath::mathmlize(MathStream & os) const
 {
-	os << cell(0);
+	return lyx::mathmlize(cell(0), os);
 }
 
 
diff --git a/src/mathed/InsetMathEnsureMath.h b/src/mathed/InsetMathEnsureMath.h
index ccc136a157..c8e58bbe97 100644
--- a/src/mathed/InsetMathEnsureMath.h
+++ b/src/mathed/InsetMathEnsureMath.h
@@ -36,7 +36,7 @@ public:
 	///
 	void write(WriteStream & os) const;
 	///
-	void mathmlize(MathStream &) const;
+	docstring mathmlize(MathStream &) const;
 	///
 	void infoize(odocstream & os) const;
 	///
diff --git a/src/mathed/InsetMathExFunc.cpp b/src/mathed/InsetMathExFunc.cpp
index 25c8dcbaf9..173436eb61 100644
--- a/src/mathed/InsetMathExFunc.cpp
+++ b/src/mathed/InsetMathExFunc.cpp
@@ -13,6 +13,7 @@
 #include "InsetMathExFunc.h"
 
 #include "MathData.h"
+#include "MathExtern.h"
 #include "MathStream.h"
 #include "MathSupport.h"
 #include "MetricsInfo.h"
@@ -122,10 +123,10 @@ void InsetMathExFunc::mathematica(MathematicaStream & os) const
 }
 
 
-void InsetMathExFunc::mathmlize(MathStream & os) const
+docstring InsetMathExFunc::mathmlize(MathStream & os) const
 {
 	os << "<mi>" << name_ << "</mi><mo>&af;</mo>";
-	os << cell(0);
+	return lyx::mathmlize(cell(0), os);
 }
 
 
diff --git a/src/mathed/InsetMathExFunc.h b/src/mathed/InsetMathExFunc.h
index fb6dda8b36..0517484f38 100644
--- a/src/mathed/InsetMathExFunc.h
+++ b/src/mathed/InsetMathExFunc.h
@@ -43,7 +43,7 @@ public:
 	///
 	void mathematica(MathematicaStream &) const;
 	///
-	void mathmlize(MathStream &) const;
+	docstring mathmlize(MathStream &) const;
 	///
 	void octave(OctaveStream &) const;
 	///
diff --git a/src/mathed/InsetMathExInt.cpp b/src/mathed/InsetMathExInt.cpp
index 88970e0e96..5277b6cde8 100644
--- a/src/mathed/InsetMathExInt.cpp
+++ b/src/mathed/InsetMathExInt.cpp
@@ -12,6 +12,7 @@
 
 #include "InsetMathExInt.h"
 #include "MathData.h"
+#include "MathExtern.h"
 #include "MathStream.h"
 #include "MathStream.h"
 #include "InsetMathSymbol.h"
@@ -122,7 +123,7 @@ void InsetMathExInt::mathematica(MathematicaStream & os) const
 }
 
 
-void InsetMathExInt::mathmlize(MathStream & os) const
+docstring InsetMathExInt::mathmlize(MathStream & os) const
 {
 	// At the moment, we are not extracting sums and the like for MathML.
 	// If we should decide to do so later, then we'll need to re-merge
@@ -150,9 +151,11 @@ void InsetMathExInt::mathmlize(MathStream & os) const
 		os << ETag("msub");
 	else if (upper)
 		os << ETag("msup");
-	os << cell(0) << "<mo> &InvisibleTimes; </mo>"
+	docstring rv = lyx::mathmlize(cell(0), os);
+	os << "<mo> &InvisibleTimes; </mo>"
 	   << MTag("mrow") << "<mo> &DifferentialD; </mo>"
 	   << cell(1) << ETag("mrow");
+	return rv;
 }
 
 
diff --git a/src/mathed/InsetMathExInt.h b/src/mathed/InsetMathExInt.h
index ced825b890..55aa1f78f2 100644
--- a/src/mathed/InsetMathExInt.h
+++ b/src/mathed/InsetMathExInt.h
@@ -52,7 +52,7 @@ public:
 	///
 	void mathematica(MathematicaStream &) const;
 	///
-	void mathmlize(MathStream &) const;
+	docstring mathmlize(MathStream &) const;
 	///
 	void write(WriteStream & os) const;
 	///
diff --git a/src/mathed/InsetMathFrac.cpp b/src/mathed/InsetMathFrac.cpp
index 11d24469db..3fbd56d8fd 100644
--- a/src/mathed/InsetMathFrac.cpp
+++ b/src/mathed/InsetMathFrac.cpp
@@ -17,6 +17,7 @@
 #include "Cursor.h"
 #include "LaTeXFeatures.h"
 #include "MathData.h"
+#include "MathExtern.h"
 #include "MathStream.h"
 #include "MathSupport.h"
 #include "MetricsInfo.h"
@@ -384,12 +385,14 @@ void InsetMathFrac::octave(OctaveStream & os) const
 }
 
 
-void InsetMathFrac::mathmlize(MathStream & os) const
+docstring InsetMathFrac::mathmlize(MathStream & os) const
 {
-	os << MTag("mfrac")
-	   << MTag("mrow") << cell(0) << ETag("mrow")
-		 << MTag("mrow") << cell(1) << ETag("mrow")
-		 << ETag("mfrac");
+	os << MTag("mfrac") << MTag("mrow");
+	docstring rv = lyx::mathmlize(cell(0), os);
+	os << ETag("mrow") << MTag("mrow");
+	rv += lyx::mathmlize(cell(1), os);
+	os << ETag("mrow") << ETag("mfrac");
+	return rv;
 }
 
 
@@ -533,8 +536,9 @@ void InsetMathBinom::normalize(NormalStream & os) const
 }
 
 
-void InsetMathBinom::mathmlize(MathStream & os) const
+docstring InsetMathBinom::mathmlize(MathStream & os) const
 {
+	// FIXME This all needs fixing
 	switch (kind_) {
 	case BINOM:
 		os << MTag("mbinom") << cell(0) << cell(1) << ETag("mbinom");
@@ -547,6 +551,7 @@ void InsetMathBinom::mathmlize(MathStream & os) const
 		os << MTag("mdbinom") << cell(0) << cell(1) << ETag("mdbinom");
 		break;
 	}
+	return docstring();
 }
 
 
diff --git a/src/mathed/InsetMathFrac.h b/src/mathed/InsetMathFrac.h
index 36e7ba363b..14af2f8be3 100644
--- a/src/mathed/InsetMathFrac.h
+++ b/src/mathed/InsetMathFrac.h
@@ -82,7 +82,7 @@ public:
 	///
 	void octave(OctaveStream &) const;
 	///
-	void mathmlize(MathStream &) const;
+	docstring mathmlize(MathStream &) const;
 	///
 	void validate(LaTeXFeatures & features) const;
 public:
@@ -121,7 +121,7 @@ public:
 	///
 	bool extraBraces() const;
 	///
-	void mathmlize(MathStream &) const;
+	docstring mathmlize(MathStream &) const;
 	///
 	void validate(LaTeXFeatures & features) const;
 	///
diff --git a/src/mathed/InsetMathGrid.cpp b/src/mathed/InsetMathGrid.cpp
index 432a39a2f2..c4fa241857 100644
--- a/src/mathed/InsetMathGrid.cpp
+++ b/src/mathed/InsetMathGrid.cpp
@@ -14,6 +14,7 @@
 #include "InsetMathGrid.h"
 
 #include "MathData.h"
+#include "MathExtern.h"
 #include "MathParser.h"
 #include "MathStream.h"
 #include "MetricsInfo.h"
@@ -967,19 +968,21 @@ void InsetMathGrid::normalize(NormalStream & os) const
 }
 
 
-void InsetMathGrid::mathmlize(MathStream & os) const
+docstring InsetMathGrid::mathmlize(MathStream & os) const
 {
 	bool const havetable = nrows() > 1;
 	if (havetable)
 		os << MTag("mtable");
+	docstring rv;
 	for (row_type row = 0; row < nrows(); ++row) {
 		os << MTag("mrow");
 		for (col_type col = 0; col < ncols(); ++col)
-			os << cell(index(row, col));
+			rv += lyx::mathmlize(cell(index(row, col)), os);
 		os << ETag("mrow");
 	}
 	if (havetable)
 		os << ETag("mtable");
+	return rv;
 }
 
 
diff --git a/src/mathed/InsetMathGrid.h b/src/mathed/InsetMathGrid.h
index 926216ea1c..aaef2aaa21 100644
--- a/src/mathed/InsetMathGrid.h
+++ b/src/mathed/InsetMathGrid.h
@@ -219,7 +219,7 @@ public:
 	///
 	//void maple(MapleStream &) const;
 	///
-	void mathmlize(MathStream &) const;
+	docstring mathmlize(MathStream &) const;
 	///
 	//void octave(OctaveStream &) const;
 
diff --git a/src/mathed/InsetMathHull.cpp b/src/mathed/InsetMathHull.cpp
index 57137db2f2..492e748d79 100644
--- a/src/mathed/InsetMathHull.cpp
+++ b/src/mathed/InsetMathHull.cpp
@@ -1092,9 +1092,9 @@ void InsetMathHull::normalize(NormalStream & os) const
 }
 
 
-void InsetMathHull::mathmlize(MathStream & os) const
+docstring InsetMathHull::mathmlize(MathStream & os) const
 {
-	InsetMathGrid::mathmlize(os);
+	return InsetMathGrid::mathmlize(os);
 }
 
 
@@ -1782,9 +1782,9 @@ docstring InsetMathHull::xhtml(XHTMLStream & xs, OutputParams const &) const
 		xs << StartTag("math", 
 		        "display=\"block\" xmlns=\"http://www.w3.org/1998/Math/MathML\"", true);
 	MathStream ms(xs.os());
-	InsetMathGrid::mathmlize(ms);
+	docstring const rv = InsetMathGrid::mathmlize(ms);
 	xs << EndTag("math");
-	return docstring();
+	return rv;
 }
 
 
diff --git a/src/mathed/InsetMathHull.h b/src/mathed/InsetMathHull.h
index db4d2ff89c..a48edd1da5 100644
--- a/src/mathed/InsetMathHull.h
+++ b/src/mathed/InsetMathHull.h
@@ -102,7 +102,7 @@ public:
 	///
 	void write(WriteStream & os) const;
 	///
-	void mathmlize(MathStream &) const;
+	docstring mathmlize(MathStream &) const;
 	///
 	void normalize(NormalStream &) const;
 	///
diff --git a/src/mathed/InsetMathKern.cpp b/src/mathed/InsetMathKern.cpp
index 7f990f9968..fddecfe58e 100644
--- a/src/mathed/InsetMathKern.cpp
+++ b/src/mathed/InsetMathKern.cpp
@@ -73,4 +73,10 @@ void InsetMathKern::normalize(NormalStream & os) const
 }
 
 
+docstring InsetMathKern::mathmlize(MathStream &) const
+{
+	return docstring();
+}
+
+
 } // namespace lyx
diff --git a/src/mathed/InsetMathKern.h b/src/mathed/InsetMathKern.h
index bd26e4e021..db701cf158 100644
--- a/src/mathed/InsetMathKern.h
+++ b/src/mathed/InsetMathKern.h
@@ -39,7 +39,7 @@ public:
 	///
 	void normalize(NormalStream & ns) const;
 	///
-	void mathmlize(MathStream &) const { }
+	docstring mathmlize(MathStream &) const;
 	///
 	InsetCode lyxCode() const { return MATH_KERN_CODE; }
 
diff --git a/src/mathed/InsetMathLim.cpp b/src/mathed/InsetMathLim.cpp
index a5eae28bb7..91335f3c3b 100644
--- a/src/mathed/InsetMathLim.cpp
+++ b/src/mathed/InsetMathLim.cpp
@@ -12,6 +12,7 @@
 
 #include "InsetMathLim.h"
 #include "MathData.h"
+#include "MathExtern.h"
 #include "MathStream.h"
 
 #include "support/debug.h"
@@ -71,13 +72,16 @@ void InsetMathLim::mathematica(MathematicaStream & os) const
 }
 
 
-void InsetMathLim::mathmlize(MathStream & os) const
+docstring	InsetMathLim::mathmlize(MathStream & os) const
 {
 	// FIXME XHTML We need a form of MTag that takes attributes.
 	os << "<munder>"
 	   << "<mo form='prefix'>" << "lim" << "</mo>"
-	   << "<mrow>" << cell(1) << "<mo>&rarr;</mo>" << cell(2) << "</mrow></munder>"
-	   << "<mo>(</mo>" << cell(0) << "<mo>)</mo>" ; 
+		 << "<mrow>" << cell(1) << "<mo>&rarr;</mo>" << cell(2)
+		 << "</mrow></munder>" << "<mo>(</mo>";
+	docstring const rv = lyx::mathmlize(cell(0), os);
+	os << "<mo>)</mo>";
+	return rv;
 }
 
 
diff --git a/src/mathed/InsetMathLim.h b/src/mathed/InsetMathLim.h
index 11d18dc06e..5d1f1a4c6a 100644
--- a/src/mathed/InsetMathLim.h
+++ b/src/mathed/InsetMathLim.h
@@ -40,7 +40,7 @@ public:
 	///
 	void mathematica(MathematicaStream &) const;
 	///
-	void mathmlize(MathStream &) const;
+	docstring mathmlize(MathStream &) const;
 	///
 	void write(WriteStream & os) const;
 	///
diff --git a/src/mathed/InsetMathMatrix.cpp b/src/mathed/InsetMathMatrix.cpp
index d368f217b7..7b73d3803e 100644
--- a/src/mathed/InsetMathMatrix.cpp
+++ b/src/mathed/InsetMathMatrix.cpp
@@ -12,6 +12,7 @@
 
 #include "InsetMathMatrix.h"
 #include "MathData.h"
+#include "MathExtern.h"
 #include "MathStream.h"
 
 
@@ -89,20 +90,25 @@ void InsetMathMatrix::mathematica(MathematicaStream & os) const
 }
 
 
-void InsetMathMatrix::mathmlize(MathStream & os) const
+docstring InsetMathMatrix::mathmlize(MathStream & os) const
 {
 	os << "<mo form='prefix' fence='true' stretchy='true' symmetric='true' lspace='thinmathspace'>"
 	   << left_ << "</mo>";
 	os << MTag("mtable");
+	docstring rv;
 	for (row_type row = 0; row < nrows(); ++row) {
 		os << MTag("mtr");
-		for (col_type col = 0; col < ncols(); ++col)
-			os << MTag("mtd") << cell(index(row, col)) << ETag("mtd");
+		for (col_type col = 0; col < ncols(); ++col) {
+			os << MTag("mtd");
+			rv += lyx::mathmlize(cell(index(row, col)), os);
+			os << ETag("mtd");
+		}
 		os << ETag("mtr");
 	}
 	os << ETag("mtable");
 	os << "<mo form='postfix' fence='true' stretchy='true' symmetric='true' lspace='thinmathspace'>"
 	   << right_ << "</mo>";
+	return rv;
 }
 
 
diff --git a/src/mathed/InsetMathMatrix.h b/src/mathed/InsetMathMatrix.h
index a62c8ea44b..e9639811c8 100644
--- a/src/mathed/InsetMathMatrix.h
+++ b/src/mathed/InsetMathMatrix.h
@@ -40,7 +40,7 @@ public:
 	///
 	void mathematica(MathematicaStream &) const;
 	///
-	void mathmlize(MathStream &) const;
+	docstring mathmlize(MathStream &) const;
 	///
 	void octave(OctaveStream &) const;
 	///
diff --git a/src/mathed/InsetMathNumber.cpp b/src/mathed/InsetMathNumber.cpp
index fdacf0c7bc..eb2e85bdc7 100644
--- a/src/mathed/InsetMathNumber.cpp
+++ b/src/mathed/InsetMathNumber.cpp
@@ -67,9 +67,10 @@ void InsetMathNumber::octave(OctaveStream & os) const
 }
 
 
-void InsetMathNumber::mathmlize(MathStream & os) const
+docstring InsetMathNumber::mathmlize(MathStream & os) const
 {
 	os << "<mn> " << str_ << " </mn>";
+	return docstring();
 }
 
 
diff --git a/src/mathed/InsetMathNumber.h b/src/mathed/InsetMathNumber.h
index a6ca9dae29..ed9e95ffcb 100644
--- a/src/mathed/InsetMathNumber.h
+++ b/src/mathed/InsetMathNumber.h
@@ -43,7 +43,7 @@ public:
 	///
 	void mathematica(MathematicaStream &) const;
 	///
-	void mathmlize(MathStream &) const;
+	docstring mathmlize(MathStream &) const;
 	///
 	void write(WriteStream & os) const;
 	///
diff --git a/src/mathed/InsetMathRoot.cpp b/src/mathed/InsetMathRoot.cpp
index 38c09469c9..7ca7706ba0 100644
--- a/src/mathed/InsetMathRoot.cpp
+++ b/src/mathed/InsetMathRoot.cpp
@@ -13,6 +13,7 @@
 
 #include "InsetMathRoot.h"
 #include "MathData.h"
+#include "MathExtern.h"
 #include "MathStream.h"
 #include "Cursor.h"
 
@@ -112,9 +113,13 @@ void InsetMathRoot::octave(OctaveStream & os) const
 }
 
 
-void InsetMathRoot::mathmlize(MathStream & os) const
+docstring InsetMathRoot::mathmlize(MathStream & os) const
 {
-	os << MTag("mroot") << cell(1) << cell(0) << ETag("mroot");
+	os << MTag("mroot");
+	docstring rv = lyx::mathmlize(cell(1), os);
+	rv += lyx::mathmlize(cell(0), os);
+	os << ETag("mroot");
+	return rv;
 }
 
 
diff --git a/src/mathed/InsetMathRoot.h b/src/mathed/InsetMathRoot.h
index cfcac0a7f3..e05cc807a3 100644
--- a/src/mathed/InsetMathRoot.h
+++ b/src/mathed/InsetMathRoot.h
@@ -36,7 +36,7 @@ public:
 	///
 	void normalize(NormalStream &) const;
 	///
-	void mathmlize(MathStream &) const;
+	docstring mathmlize(MathStream &) const;
 	///
 	void maple(MapleStream &) const;
 	///
diff --git a/src/mathed/InsetMathScript.cpp b/src/mathed/InsetMathScript.cpp
index 1af0e57345..74420279cb 100644
--- a/src/mathed/InsetMathScript.cpp
+++ b/src/mathed/InsetMathScript.cpp
@@ -18,6 +18,7 @@
 #include "InsetMathScript.h"
 #include "InsetMathSymbol.h"
 #include "MathData.h"
+#include "MathExtern.h"
 #include "MathStream.h"
 #include "MathSupport.h"
 
@@ -616,7 +617,7 @@ void InsetMathScript::mathematica(MathematicaStream & os) const
 // It may be worth trying to output munder, mover, and munderover
 // in certain cases, e.g., for display formulas. But then we would
 // need to know if we're in a display formula.
-void InsetMathScript::mathmlize(MathStream & os) const
+docstring InsetMathScript::mathmlize(MathStream & os) const
 {
 	bool d = hasDown() && down().size();
 	bool u = hasUp() && up().size();
@@ -628,9 +629,12 @@ void InsetMathScript::mathmlize(MathStream & os) const
 	else if (d)
 		os << MTag("msub");
 
-	if (nuc().size())
-		os << MTag("mrow") << nuc() << ETag("mrow");
-	else
+	docstring rv;
+	if (nuc().size()) {
+		os << MTag("mrow");
+		rv = lyx::mathmlize(nuc(), os);
+		os << ETag("mrow");
+	} else
 		os << "<mrow />";
 
 	if (u && d)
@@ -641,6 +645,7 @@ void InsetMathScript::mathmlize(MathStream & os) const
 		os << MTag("mrow") << up() << ETag("mrow") << ETag("msup");
 	else if (d)
 		os << MTag("mrow") << down() << ETag("mrow") << ETag("msub");
+	return rv;
 }
 
 
diff --git a/src/mathed/InsetMathScript.h b/src/mathed/InsetMathScript.h
index 569bc79f35..8d704dca9f 100644
--- a/src/mathed/InsetMathScript.h
+++ b/src/mathed/InsetMathScript.h
@@ -61,7 +61,7 @@ public:
 	/// write content as something readable by Mathematica
 	void mathematica(MathematicaStream &) const;
 	/// write content as something resembling MathML
-	void mathmlize(MathStream &) const;
+	docstring mathmlize(MathStream &) const;
 	/// write content as something readable by Octave
 	void octave(OctaveStream &) const;
 
diff --git a/src/mathed/InsetMathSpace.cpp b/src/mathed/InsetMathSpace.cpp
index c771d2595b..b2a321234d 100644
--- a/src/mathed/InsetMathSpace.cpp
+++ b/src/mathed/InsetMathSpace.cpp
@@ -192,11 +192,11 @@ void InsetMathSpace::octave(OctaveStream & os) const
 }
 
 
-void InsetMathSpace::mathmlize(MathStream & ms) const
+docstring InsetMathSpace::mathmlize(MathStream & ms) const
 {
 	SpaceInfo const & si = space_info[space_];
 	if (si.negative || !si.visible)
-		return;
+		return docstring();
 	string l;
 	if (si.custom)
 		l = length_.asHTMLString();
@@ -210,6 +210,7 @@ void InsetMathSpace::mathmlize(MathStream & ms) const
 	if (!l.empty())
 		ms << " width=\"" << from_ascii(l) << "\"";
 	ms << " />";
+	return docstring();
 }
 
 	
diff --git a/src/mathed/InsetMathSpace.h b/src/mathed/InsetMathSpace.h
index 3e60b41c12..442fe2e799 100644
--- a/src/mathed/InsetMathSpace.h
+++ b/src/mathed/InsetMathSpace.h
@@ -52,7 +52,7 @@ public:
 	///
 	void octave(OctaveStream &) const;
 	///
-	void mathmlize(MathStream & ms) const;
+	docstring mathmlize(MathStream & ms) const;
 	///
 	void write(WriteStream & os) const;
 	/// generate something that will be understood by the Dialogs.
diff --git a/src/mathed/InsetMathSpecialChar.cpp b/src/mathed/InsetMathSpecialChar.cpp
index 2c600d0c2b..b32c2e2302 100644
--- a/src/mathed/InsetMathSpecialChar.cpp
+++ b/src/mathed/InsetMathSpecialChar.cpp
@@ -147,7 +147,7 @@ void InsetMathSpecialChar::octave(OctaveStream & os) const
 }
 
 
-void InsetMathSpecialChar::mathmlize(MathStream & ms) const
+docstring InsetMathSpecialChar::mathmlize(MathStream & ms) const
 {
 	switch (char_) {
 	case '&':
@@ -157,6 +157,7 @@ void InsetMathSpecialChar::mathmlize(MathStream & ms) const
 		ms.os().put(char_);
 		break;
 	}
+	return docstring();
 }
 
 
diff --git a/src/mathed/InsetMathSpecialChar.h b/src/mathed/InsetMathSpecialChar.h
index c672b504f6..5dcc012801 100644
--- a/src/mathed/InsetMathSpecialChar.h
+++ b/src/mathed/InsetMathSpecialChar.h
@@ -45,7 +45,7 @@ public:
 	///
 	void mathematica(MathematicaStream &) const;
 	///
-	void mathmlize(MathStream & ms) const;
+	docstring mathmlize(MathStream & ms) const;
 	/// identifies SpecialChar insets
 	InsetMathSpecialChar const * asSpecialCharInset() const { return this; }
 	///
diff --git a/src/mathed/InsetMathSqrt.cpp b/src/mathed/InsetMathSqrt.cpp
index f738e2c17b..dc154f8f6b 100644
--- a/src/mathed/InsetMathSqrt.cpp
+++ b/src/mathed/InsetMathSqrt.cpp
@@ -12,6 +12,7 @@
 
 #include "InsetMathSqrt.h"
 #include "MathData.h"
+#include "MathExtern.h"
 #include "MathStream.h"
 #include "TextPainter.h"
 #include "frontends/Painter.h"
@@ -107,9 +108,12 @@ void InsetMathSqrt::octave(OctaveStream & os) const
 }
 
 
-void InsetMathSqrt::mathmlize(MathStream & os) const
+docstring InsetMathSqrt::mathmlize(MathStream & os) const
 {
-	os << MTag("msqrt") << cell(0) << ETag("msqrt");
+	os << MTag("msqrt");
+	docstring const rv = lyx::mathmlize(cell(0), os);
+	os << ETag("msqrt");
+	return rv;
 }
 
 
diff --git a/src/mathed/InsetMathSqrt.h b/src/mathed/InsetMathSqrt.h
index 485f66a574..2cdc0e5a37 100644
--- a/src/mathed/InsetMathSqrt.h
+++ b/src/mathed/InsetMathSqrt.h
@@ -44,7 +44,7 @@ public:
 	///
 	void octave(OctaveStream &) const;
 	///
-	void mathmlize(MathStream &) const;
+	docstring mathmlize(MathStream &) const;
 	///
 	InsetCode lyxCode() const { return MATH_SQRT_CODE; }
 
diff --git a/src/mathed/InsetMathString.cpp b/src/mathed/InsetMathString.cpp
index ac951a1838..28069ca6ad 100644
--- a/src/mathed/InsetMathString.cpp
+++ b/src/mathed/InsetMathString.cpp
@@ -89,13 +89,6 @@ void InsetMathString::octave(OctaveStream & os) const
 }
 
 
-void InsetMathString::mathmlize(MathStream & /*os*/) const
-{
-	// useless, no doubt, but we should not be here
-	LASSERT(false, /* */);
-}
-
-
 void InsetMathString::write(WriteStream & os) const
 {
 	if (!os.latex() || os.lockedMode()) {
diff --git a/src/mathed/InsetMathString.h b/src/mathed/InsetMathString.h
index 9f94a7457f..95b2937c1c 100644
--- a/src/mathed/InsetMathString.h
+++ b/src/mathed/InsetMathString.h
@@ -47,8 +47,6 @@ public:
 	///
 	void mathematica(MathematicaStream &) const;
 	///
-	void mathmlize(MathStream &) const;
-	///
 	void write(WriteStream & os) const;
 	///
 	InsetCode lyxCode() const { return MATH_STRING_CODE; }
diff --git a/src/mathed/InsetMathSymbol.cpp b/src/mathed/InsetMathSymbol.cpp
index a4a761171f..d09d40b02c 100644
--- a/src/mathed/InsetMathSymbol.cpp
+++ b/src/mathed/InsetMathSymbol.cpp
@@ -184,7 +184,7 @@ char const * MathMLtype(docstring const & s)
 }
 
 
-void InsetMathSymbol::mathmlize(MathStream & os) const
+docstring InsetMathSymbol::mathmlize(MathStream & os) const
 {
 	// FIXME To get this working properly, we need to do add the 
 	// XML entity definitions to lib/symbols. And probably do more
@@ -197,6 +197,7 @@ void InsetMathSymbol::mathmlize(MathStream & os) const
 	else
 		os << sym_->xmlname;
 	os << " </" << type << '>';
+	return docstring();
 }
 
 
diff --git a/src/mathed/InsetMathSymbol.h b/src/mathed/InsetMathSymbol.h
index 5382f72e85..a9b96fc4b5 100644
--- a/src/mathed/InsetMathSymbol.h
+++ b/src/mathed/InsetMathSymbol.h
@@ -61,7 +61,7 @@ public:
 	///
 	void mathematica(MathematicaStream &) const;
 	///
-	void mathmlize(MathStream &) const;
+	docstring mathmlize(MathStream &) const;
 	///
 	void octave(OctaveStream &) const;
 	///
diff --git a/src/mathed/InsetMathUnknown.cpp b/src/mathed/InsetMathUnknown.cpp
index 2cd11c2a86..ae6f8ce005 100644
--- a/src/mathed/InsetMathUnknown.cpp
+++ b/src/mathed/InsetMathUnknown.cpp
@@ -86,9 +86,10 @@ void InsetMathUnknown::mathematica(MathematicaStream & os) const
 }
 
 
-void InsetMathUnknown::mathmlize(MathStream & os) const
+docstring InsetMathUnknown::mathmlize(MathStream & os) const
 {
 	os << MTag("mi") << name_ << ETag("mi");
+	return docstring();
 }
 
 
diff --git a/src/mathed/InsetMathUnknown.h b/src/mathed/InsetMathUnknown.h
index b43bcfd672..9493ecfc28 100644
--- a/src/mathed/InsetMathUnknown.h
+++ b/src/mathed/InsetMathUnknown.h
@@ -50,7 +50,7 @@ public:
 	///
 	void mathematica(MathematicaStream &) const;
 	///
-	void mathmlize(MathStream &) const;
+	docstring mathmlize(MathStream &) const;
 	///
 	void octave(OctaveStream &) const;
 	///
diff --git a/src/mathed/MathExtern.cpp b/src/mathed/MathExtern.cpp
index f9b9f42af2..ee7ceebe4f 100644
--- a/src/mathed/MathExtern.cpp
+++ b/src/mathed/MathExtern.cpp
@@ -1413,20 +1413,22 @@ void mathematica(MathData const & dat, MathematicaStream & os)
 }
 
 
-void mathmlize(MathData const & dat, MathStream & os)
+docstring mathmlize(MathData const & dat, MathStream & os)
 {
 	MathData ar = dat;
 	extractStructure(ar, MATHML);
+	docstring retval;
 	if (ar.size() == 0)
 		os << "<mrow/>";
 	else if (ar.size() == 1)
-		os << ar.front();
+		retval = ar.front()->mathmlize(os);
 	else {
 		os << MTag("mrow");
 		for (MathData::const_iterator it = ar.begin(); it != ar.end(); ++it)
-			(*it)->mathmlize(os);
+			retval += (*it)->mathmlize(os);
 		os << ETag("mrow");
 	}
+	return retval;
 }
 
 // convert this inset somehow to a number
diff --git a/src/mathed/MathExtern.h b/src/mathed/MathExtern.h
index 199295ae96..d367b1e901 100644
--- a/src/mathed/MathExtern.h
+++ b/src/mathed/MathExtern.h
@@ -30,7 +30,7 @@ void normalize(MathData const &, NormalStream &);
 void maple(MathData const &, MapleStream &);
 void maxima(MathData const &, MaximaStream &);
 void mathematica(MathData const &, MathematicaStream &);
-void mathmlize(MathData const &, MathStream &);
+docstring mathmlize(MathData const &, MathStream &);
 void octave(MathData const &, OctaveStream &);
 
 bool extractNumber(MathData const & ar, int & i);
diff --git a/src/mathed/MathMacro.cpp b/src/mathed/MathMacro.cpp
index 5564600d06..dd7ccf3e71 100644
--- a/src/mathed/MathMacro.cpp
+++ b/src/mathed/MathMacro.cpp
@@ -73,7 +73,10 @@ public:
 	}
 	// FIXME Other external things need similar treatment.
 	///
-	void mathmlize(MathStream & ms) const { ms << mathMacro_.cell(idx_); }
+	docstring mathmlize(MathStream & ms) const {
+		ms << mathMacro_.cell(idx_);
+		return docstring();
+	}
 	///
 	void draw(PainterInfo & pi, int x, int y) const {
 		if (mathMacro_.editMetrics(pi.base.bv)) {
@@ -740,9 +743,10 @@ void MathMacro::maple(MapleStream & os) const
 }
 
 
-void MathMacro::mathmlize(MathStream & os) const
+docstring MathMacro::mathmlize(MathStream & os) const
 {
 	os << expanded_.cell(0);
+	return docstring();
 }
 
 
diff --git a/src/mathed/MathMacro.h b/src/mathed/MathMacro.h
index b431a9a9a5..bb9ed723ca 100644
--- a/src/mathed/MathMacro.h
+++ b/src/mathed/MathMacro.h
@@ -71,7 +71,7 @@ public:
 	///
 	void maple(MapleStream &) const;
 	///
-	void mathmlize(MathStream &) const;
+	docstring mathmlize(MathStream &) const;
 	///
 	void octave(OctaveStream &) const;
 	///