Implement to_utf8_string().

* src/ltlvisit/tostring.cc, src/ltlvisit/tostring.hh: Here.
* src/ltltest/randltl.cc: Add option -8 to display utf-8 formulae.
* src/ltltest/utf8.test: Test it.

src/ltltest/randltl.cc

@@ -1,8 +1,9 @@
-// Copyright (C) 2008, 2009, 2011 Laboratoire de Recherche et Développement
+// -*- coding: utf-8 -*-
-// de l'Epita (LRDE).
+// Copyright (C) 2008, 2009, 2011, 2012 Laboratoire de Recherche et
+// Développement de l'Epita (LRDE).
 // Copyright (C) 2003, 2005 Laboratoire d'Informatique de
-// Paris 6 (LIP6), département Systèmes Répartis Coopératifs (SRC),
+// Paris 6 (LIP6), département Systèmes Répartis Coopératifs (SRC),
-// Université Pierre et Marie Curie.
+// Université Pierre et Marie Curie.
 //
 // This file is part of Spot, a model checking library.
 //
@@ -47,6 +48,7 @@ syntax(char* prog)
 	    << "  -P      generate PSL formulae" << std::endl
 	    << std::endl
 	    << "Options:" << std::endl
+	    << "  -8      output in UTF-8" << std::endl
 	    << "  -d      dump priorities, do not generate any formula"
 	    << std::endl
 	    << "  -f  N    the size of the formula [15]" << std::endl
@@ -89,6 +91,7 @@ main(int argc, char** argv)
 {
   enum { OutputBool, OutputLTL, OutputSERE, OutputPSL } output = OutputLTL;
   bool opt_d = false;
+  bool utf8 = false;
   int opt_s = 0;
   int opt_f = 15;
   int opt_F = 1;
@@ -110,7 +113,11 @@ main(int argc, char** argv)
 
   while (++argn < argc)
     {
-      if (!strcmp(argv[argn], "-B"))
+      if (!strcmp(argv[argn], "-8"))
+	{
+	  utf8 = true;
+	}
+      else if (!strcmp(argv[argn], "-B"))
 	{
 	  output = OutputBool;
 	}
@@ -341,8 +348,9 @@ main(int argc, char** argv)
 			    << "of size " << opt_r << " or more." << std::endl;
 		  exit(2);
 		}
-	      std::string txt = spot::ltl::to_string(f, false,
+	      std::string txt = utf8
-						     output == OutputSERE);
+		? spot::ltl::to_utf8_string(f, false, output == OutputSERE)
+		: spot::ltl::to_string(f, false, output == OutputSERE);
 	      f->destroy();
 	      if (!opt_u || unique.insert(txt).second)
 		{

src/ltltest/utf8.test

@@ -70,3 +70,7 @@ ignoring trailing garbage
 
 EOF
 cmp exp err
+
+
+../randltl -P -8 -u -s 0 -f 16 a b c -F 100 > formulae
+../reduc -f -h 0 formulae

src/ltlvisit/tostring.cc

@@ -1,3 +1,4 @@
+// -*- coding: utf-8 -*-
 // Copyright (C) 2008, 2010, 2012 Laboratoire de Recherche et
 // Développement de l'Epita (LRDE)
 // Copyright (C) 2003, 2004 Laboratoire d'Informatique de Paris 6 (LIP6),
@@ -79,12 +80,12 @@ namespace spot
 	" R ",
 	" W ",
 	" M ",
-	" <>-> ",
+	"<>-> ",
-	" <>=> ",
+	"<>=> ",
-	" <>+> ",
+	"<>+> ",
-	" <>=+> ",
+	"<>=+> ",
-	" []-> ",
+	"[]-> ",
-	" []=> ",
+	"[]=> ",
 	"!",
 	"X",
 	"F",
@@ -109,12 +110,12 @@ namespace spot
 	" V ",
 	" W ",			// not supported
 	" M ",			// not supported
-	" <>-> ",		// not supported
+	"<>-> ",		// not supported
-	" <>=> ",		// not supported
+	"<>=> ",		// not supported
-	" <>+> ",		// not supported
+	"<>+> ",		// not supported
-	" <>=+> ",		// not supported
+	"<>=+> ",		// not supported
-	" []-> ",		// not supported
+	"[]-> ",		// not supported
-	" []=> ",		// not supported
+	"[]=> ",		// not supported
 	"!",
 	"()",
 	"<>",
@@ -128,6 +129,36 @@ namespace spot
 	":",			// not supported
       };
 
+      const char* utf8_kw[] = {
+	"0",
+	"1",
+	"[*0]",
+	"⊕",
+	" → ",
+	" ↔ ",
+	" U ",
+	" R ",
+	" W ",
+	" M ",
+	"◇→ ",
+	"◇⇒ ",
+	"◇→̃ ",
+	"◇⇒̃ ",
+	"□→ ",
+	"□⇒ ",
+	"¬",
+	"○",
+	"◇",
+	"□",
+	"∨",
+	" | ",
+	"∧",
+	" ∩ ",
+	" & ",
+	";",
+	":",
+      };
+
       static bool
       is_bare_word(const char* str)
       {
@@ -491,7 +522,8 @@ namespace spot
 	      top_level_ = true;
 	      break;
 	    case unop::NegClosure:
-	      os_ << "!{";
+	      emit(KNot);
+	      os_ << "{";
 	      in_ratexp_ = true;
 	      top_level_ = true;
 	      break;
@@ -684,6 +716,23 @@ namespace spot
       return os.str();
     }
 
+    std::ostream&
+    to_utf8_string(const formula* f, std::ostream& os, bool full_parent,
+	      bool ratexp)
+    {
+      to_string_visitor v(os, full_parent, ratexp, utf8_kw);
+      f->accept(v);
+      return os;
+    }
+
+    std::string
+    to_utf8_string(const formula* f, bool full_parent, bool ratexp)
+    {
+      std::ostringstream os;
+      to_utf8_string(f, os, full_parent, ratexp);
+      return os.str();
+    }
+
     std::ostream&
     to_spin_string(const formula* f, std::ostream& os, bool full_parent)
     {

src/ltlvisit/tostring.hh

@@ -1,7 +1,8 @@
-// Copyright (C) 2010, 2011 Laboratoire de Recherche et Développement de
+// -*- coding: utf-8 -*-
-// l'Epita (LRDE).
+// Copyright (C) 2010, 2011, 2012 Laboratoire de Recherche et
+// Développement de l'Epita (LRDE).
 // Copyright (C) 2003, 2004  Laboratoire d'Informatique de Paris 6 (LIP6),
-// département Systèmes Répartis Coopératifs (SRC), Université Pierre
+// département Systèmes Répartis Coopératifs (SRC), Université Pierre
 // et Marie Curie.
 //
 // This file is part of Spot, a model checking library.
@@ -54,6 +55,27 @@ namespace spot
     std::string
     to_string(const formula* f, bool full_parent = false, bool ratexp = false);
 
+    /// \brief Output a formula as an utf8 string which is parsable unless
+    /// the formula contains automaton operators (used in ELTL formulae).
+    /// \param f The formula to translate.
+    /// \param os The stream where it should be output.
+    /// \param full_parent Whether or not the string should by fully
+    ///			   parenthesized.
+    /// \param ratexp Whether we are printing a SERE.
+    std::ostream&
+    to_utf8_string(const formula* f, std::ostream& os, bool full_parent = false,
+	      bool ratexp = false);
+
+    /// \brief Output a formula as an utf8 string which is parsable
+    /// unless the formula contains automaton operators (used in ELTL formulae).
+    /// \param f The formula to translate.
+    /// \param full_parent Whether or not the string should by fully
+    ///			   parenthesized.
+    /// \param ratexp Whether we are printing a SERE.
+    std::string
+    to_utf8_string(const formula* f, bool full_parent = false,
+		   bool ratexp = false);
+
     /// \brief Output a formula as a (parsable by Spin) string.
     /// \param f The formula to translate.
     /// \param os The stream where it should be output.