Possibility to specify a preset argument

This will be needed for beamer plain and fragile frame support.

lib/doc/Customization.lyx

@@ -10748,7 +10748,7 @@ status collapsed
 
 \begin_layout Itemize
 
-\change_inserted -712698321 1354263106
+\change_inserted -712698321 1355144479
 \begin_inset Flex Code
 status collapsed
 
@@ -10810,6 +10810,39 @@ status collapsed
 \end_inset
 
 .
+\end_layout
+
+\begin_layout Itemize
+
+\change_inserted -712698321 1355144578
+\begin_inset Flex Code
+status collapsed
+
+\begin_layout Plain Layout
+
+\change_inserted -712698321 1355144487
+PresetArg
+\change_unchanged
+
+\end_layout
+
+\end_inset
+
+ 
+\begin_inset Flex Code
+status collapsed
+
+\begin_layout Plain Layout
+
+\change_inserted -712698321 1355144500
+[string]
+\end_layout
+
+\end_inset
+
+ defines an argument that is inserted in any case (alone or in addition
+ to user-specified arguments).
+ Multiple arguments need to be separated by comma.
 \change_unchanged
 
 \end_layout
@@ -12494,7 +12527,42 @@ LatexName
 \end_inset
 
  stuff.
- This parameter cannot be changed from within LyX.
+ This parameter cannot be changed from within LyX
+\change_inserted -712698321 1355144804
+ (use 
+\begin_inset Flex Code
+status collapsed
+
+\begin_layout Plain Layout
+
+\change_inserted -712698321 1355144804
+Argument
+\end_layout
+
+\end_inset
+
+ for customizable parameters)
+\change_unchanged
+.
+
+\change_inserted -712698321 1355144804
+ This will be output as is after all LaTeX 
+\begin_inset Flex Code
+status collapsed
+
+\begin_layout Plain Layout
+
+\change_inserted -712698321 1355144658
+Arguments
+\change_unchanged
+
+\end_layout
+
+\end_inset
+
+.
+\change_unchanged
+
 \end_layout
 
 \begin_layout Description
@@ -16636,7 +16704,40 @@ status collapsed
 \end_inset
 
 .
- This parameter cannot be changed from within LyX.
+ 
+\change_inserted -712698321 1355144715
+This will be output as is after all LaTeX 
+\begin_inset Flex Code
+status collapsed
+
+\begin_layout Plain Layout
+
+\change_inserted -712698321 1355144713
+Arguments
+\end_layout
+
+\end_inset
+
+.
+ 
+\change_unchanged
+This parameter cannot be changed from within LyX
+\change_inserted -712698321 1355144775
+ (use 
+\begin_inset Flex Code
+status collapsed
+
+\begin_layout Plain Layout
+
+\change_inserted -712698321 1355144747
+Argument
+\end_layout
+
+\end_inset
+
+ for customizable parameters)
+\change_unchanged
+.
 \end_layout
 
 \begin_layout Description

src/Layout.cpp

@@ -916,6 +916,9 @@ void Layout::readArgument(Lexer & lex)
 			arg.rdelim = lex.getDocString();
 			arg.rdelim = support::subst(arg.rdelim, from_ascii("<br/>"),
 						    from_ascii("\n"));
+		} else if (tok == "presetarg") {
+			lex.next();
+			arg.presetarg = lex.getDocString();
 		} else if (tok == "tooltip") {
 			lex.next();
 			arg.tooltip = lex.getDocString();

src/Layout.h

@@ -94,6 +94,7 @@ public:
 		bool mandatory;
 		docstring ldelim;
 		docstring rdelim;
+		docstring presetarg;
 		docstring tooltip;
 		std::string requires;
 		std::string decoration;

src/insets/InsetArgument.cpp

@@ -239,7 +239,7 @@ InsetLayout::InsetDecoration InsetArgument::decoration() const
 
 void InsetArgument::latexArgument(otexstream & os,
 		OutputParams const & runparams_in, docstring const & ldelim,
-		docstring const & rdelim) const
+		docstring const & rdelim, docstring const & presetarg) const
 {
 	TexRow texrow;
 	odocstringstream ss;
@@ -247,6 +247,9 @@ void InsetArgument::latexArgument(otexstream & os,
 	OutputParams runparams = runparams_in;
 	InsetText::latex(ots, runparams);
 	docstring str = ss.str();
+	docstring const sep = str.empty() ? docstring() : from_ascii(", ");
+	if (!presetarg.empty())
+		str = presetarg + sep + str;
 	if (ldelim != "{" && support::contains(str, rdelim))
 		str = '{' + str + '}';
 	os << ldelim << str << rdelim;

src/insets/InsetArgument.h

@@ -31,7 +31,8 @@ public:
 
 	/// Outputting the parameter of a LaTeX command
 	void latexArgument(otexstream &, OutputParams const &,
-			docstring const&, docstring const &) const;
+			   docstring const&, docstring const &,
+			   docstring const &) const;
 
 	std::string name() const { return name_; }
 

src/insets/InsetLayout.cpp

@@ -544,6 +544,9 @@ void InsetLayout::readArgument(Lexer & lex)
 			arg.rdelim = lex.getDocString();
 			arg.rdelim = support::subst(arg.rdelim,
 						    from_ascii("<br/>"), from_ascii("\n"));
+		} else if (tok == "presetarg") {
+			lex.next();
+			arg.presetarg = lex.getDocString();
 		} else if (tok == "tooltip") {
 			lex.next();
 			arg.tooltip = lex.getDocString();

src/output_latex.cpp

@@ -368,7 +368,7 @@ void latexArgInsets(Paragraph const & par, otexstream & os,
 						ldelim = arg.ldelim;
 					if (!arg.rdelim.empty())
 						rdelim = arg.rdelim;
-					ins->latexArgument(os, runparams, ldelim, rdelim);
+					ins->latexArgument(os, runparams, ldelim, rdelim, arg.presetarg);
 					inserted = true;
 				}
 			}
@@ -385,7 +385,17 @@ void latexArgInsets(Paragraph const & par, otexstream & os,
 								from_ascii("{") : arg.ldelim;
 						docstring rdelim = arg.rdelim.empty() ?
 								from_ascii("}") : arg.rdelim;
-						os << ldelim << rdelim;
+						os << ldelim << arg.presetarg << rdelim;
+					} else if (!arg.presetarg.empty()) {
+						docstring ldelim = arg.mandatory ?
+								from_ascii("{") : from_ascii("[");
+						docstring rdelim = arg.mandatory ?
+								from_ascii("}") : from_ascii("]");
+						if (!arg.ldelim.empty())
+							ldelim = arg.ldelim;
+						if (!arg.rdelim.empty())
+							rdelim = arg.rdelim;
+						os << ldelim << arg.presetarg << rdelim;
 					} else if (find(required.begin(), required.end(),
 						   (*lait).first) != required.end()) {
 						docstring ldelim = arg.ldelim.empty() ?