diff --git a/ChangeLog b/ChangeLog
index af2421f8d..53164cc31 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+2004-05-26  Alexandre Duret-Lutz  <adl@src.lip6.fr>
+
+	* src/ltlvisit/basereduc.cc, src/ltlvisit/reducform.cc: Use
+	dynamic_cast instead of node_type_form_visitor, this is usually
+	smaller.
+	* src/ltlvisit/reducform.hh,
+	src/ltlvisit/forminf.cc (node_type_form_visitor): Delete.
+	* src/sanity/style.test: Two more checks.
+
 2004-05-25  Alexandre Duret-Lutz  <adl@src.lip6.fr>
 
 	* src/ltlvisit/formlength.cc: Rename as ...
diff --git a/src/ltlvisit/basereduc.cc b/src/ltlvisit/basereduc.cc
index 2f4bddacf..93d46760a 100644
--- a/src/ltlvisit/basereduc.cc
+++ b/src/ltlvisit/basereduc.cc
@@ -81,7 +81,7 @@ namespace spot
 	  case unop::X:
 	    // X(true) = true
 	    // X(false) = false
-	    if (node_type(result_) == (node_type_form_visitor::Const))
+	    if (dynamic_cast<constant*>(result_))
 	      return;
 
 	    // XGF(f) = GF(f)
@@ -123,10 +123,9 @@ namespace spot
 	    return;
 
 	  case unop::F:
-
 	    // F(true) = true
 	    // F(false) = false
-	    if (node_type(result_) == (node_type_form_visitor::Const))
+	    if (dynamic_cast<constant*>(result_))
 	      return;
 
 	    // FX(a) = XF(a)
@@ -177,10 +176,9 @@ namespace spot
 	    return;
 
 	  case unop::G:
-
 	    // G(true) = true
 	    // G(false) = false
-	    if (node_type(result_) == (node_type_form_visitor::Const))
+	    if (dynamic_cast<constant*>(result_))
 	      return;
 
 	    // G(a R b) = G(b)
@@ -249,8 +247,6 @@ namespace spot
 	formula* f1 = bo->first();
 	formula* f2 = bo->second();
 	formula* ftmp = NULL;
-	node_type_form_visitor v1;
-	node_type_form_visitor v2;
 	unop* fu1 = NULL;
 	unop* fu2 = NULL;
 	switch (bo->op())
@@ -275,7 +271,7 @@ namespace spot
 
 	    // a U false = false
 	    // a U true = true
-	    if (node_type(f2) == (node_type_form_visitor::Const))
+	    if (dynamic_cast<constant*>(f2))
 	      {
 		result_ = f2;
 		return;
@@ -308,7 +304,7 @@ namespace spot
 
 	    // a R false = false
 	    // a R true = true
-	    if (node_type(f2) == (node_type_form_visitor::Const))
+	    if (dynamic_cast<constant*>(f2))
 	      {
 		result_ = f2;
 		return;
@@ -358,9 +354,6 @@ namespace spot
 
 	multop::vec* tmpOther = new multop::vec;
 
-	unop* uo = NULL;
-	unop* uo2 = NULL;
-	binop* bo = NULL;
 	formula* ftmp = NULL;
 
 	for (unsigned i = 0; i < mos; ++i)
@@ -375,47 +368,43 @@ namespace spot
 	      {
 		if (*i == NULL)
 		  continue;
-		switch (node_type(*i))
+		unop* uo = dynamic_cast<unop*>(*i);
+		binop* bo = dynamic_cast<binop*>(*i);
+		if (uo)
 		  {
-
-		  case node_type_form_visitor::Unop:
-
-		    // Xa & Xb = X(a & b)
-		    uo = dynamic_cast<unop*>(*i);
 		    if (uo && uo->op() == unop::X)
 		      {
+			// Xa & Xb = X(a & b)
 			tmpX->push_back(basic_reduce_form(uo->child()));
-			break;
 		      }
-
-		    // FG(a) & FG(b) = FG(a & b)
-		    if (is_FG(*i))
+		    else if (is_FG(*i))
 		      {
-			uo2 = dynamic_cast<unop*>(uo->child());
+			// FG(a) & FG(b) = FG(a & b)
+			unop* uo2 = dynamic_cast<unop*>(uo->child());
 			tmpFG->push_back(basic_reduce_form(uo2->child()));
-			break;
 		      }
-		    tmpOther->push_back(basic_reduce_form(*i));
-		    break;
-
-		  case node_type_form_visitor::Binop:
-
-		    // (a U b) & (c U b) = (a & c) U b
-		    if (dynamic_cast<binop*>(*i)->op() == binop::U)
+		    else
 		      {
+			tmpOther->push_back(basic_reduce_form(*i));
+		      }
+		  }
+		else if (bo)
+		  {
+		    if (bo->op() == binop::U)
+		      {
+			// (a U b) & (c U b) = (a & c) U b
 			ftmp = dynamic_cast<binop*>(*i)->second();
 			tmpUright = new multop::vec;
 			for (multop::vec::iterator j = i; j != res->end(); j++)
 			  {
 			    if (!*j)
 			      continue;
-			    if (node_type(*j) == node_type_form_visitor::Binop
-				&& dynamic_cast<binop*>(*j)->op() == binop::U
-				&& ftmp == dynamic_cast<binop*>(*j)->second())
+			    binop* bo2 = dynamic_cast<binop*>(*j);
+			    if (bo2 && bo2->op() == binop::U
+				&& ftmp == bo2->second())
 			      {
-				bo = dynamic_cast<binop*>(*j);
 				tmpUright
-				  ->push_back(basic_reduce_form(bo->first()));
+				  ->push_back(basic_reduce_form(bo2->first()));
 				if (j != i)
 				  {
 				    destroy(*j);
@@ -430,25 +419,22 @@ namespace spot
 							       And,
 							       tmpUright),
 						      basic_reduce_form(ftmp)));
-			break;
 		      }
-
-		    // (a R b) & (a R c) = a R (b & c)
-		    if (dynamic_cast<binop*>(*i)->op() == binop::R)
+		    else if (bo->op() == binop::R)
 		      {
+			// (a R b) & (a R c) = a R (b & c)
 			ftmp = dynamic_cast<binop*>(*i)->first();
 			tmpRright = new multop::vec;
 			for (multop::vec::iterator j = i; j != res->end(); j++)
 			  {
 			    if (!*j)
 			      continue;
-			    if (node_type(*j) == node_type_form_visitor::Binop
-				&& dynamic_cast<binop*>(*j)->op() == binop::R
-				&& ftmp == dynamic_cast<binop*>(*j)->first())
+			    binop* bo2 = dynamic_cast<binop*>(*j);
+			    if (bo2 && bo2->op() == binop::R
+				&& ftmp == bo2->first())
 			      {
-				bo = dynamic_cast<binop*>(*j);
 				tmpRright
-				  ->push_back(basic_reduce_form(bo->second()));
+				  ->push_back(basic_reduce_form(bo2->second()));
 				if (j != i)
 				  {
 				    destroy(*j);
@@ -462,19 +448,21 @@ namespace spot
 						      multop::
 						      instance(multop::And,
 							       tmpRright)));
-			break;
 		      }
+		    else
+		      {
+			tmpOther->push_back(basic_reduce_form(*i));
+		      }
+		  }
+		else
+		  {
 		    tmpOther->push_back(basic_reduce_form(*i));
-		    break;
-		  default:
-		    tmpOther->push_back(basic_reduce_form(*i));
-		    break;
 		  }
 		destroy(*i);
 	      }
 
-	    delete(tmpGF);
-	    tmpGF = NULL;
+	    delete tmpGF;
+	    tmpGF = 0;
 
 	    break;
 
@@ -484,47 +472,43 @@ namespace spot
 	      {
 		if (!*i)
 		  continue;
-		switch (node_type(*i))
+		unop* uo = dynamic_cast<unop*>(*i);
+		binop* bo = dynamic_cast<binop*>(*i);
+		if (uo)
 		  {
-
-		  case node_type_form_visitor::Unop:
-
-		    // Xa | Xb = X(a | b)
-		    uo = dynamic_cast<unop*>(*i);
 		    if (uo && uo->op() == unop::X)
 		      {
+			// Xa | Xb = X(a | b)
 			tmpX->push_back(basic_reduce_form(uo->child()));
-			break;
 		      }
-
-		    // GF(a) | GF(b) = GF(a | b)
-		    if (is_GF(*i))
+		    else if (is_GF(*i))
 		      {
-			uo2 = dynamic_cast<unop*>(uo->child());
+			// GF(a) | GF(b) = GF(a | b)
+			unop* uo2 = dynamic_cast<unop*>(uo->child());
 			tmpGF->push_back(basic_reduce_form(uo2->child()));
-			break;
 		      }
-		    tmpOther->push_back(basic_reduce_form(*i));
-		    break;
-
-		  case node_type_form_visitor::Binop:
-
-		    // (a U b) | (a U c) = a U (b | c)
-		    if (dynamic_cast<binop*>(*i)->op() == binop::U)
+		    else
 		      {
-			ftmp = dynamic_cast<binop*>(*i)->first();
+			tmpOther->push_back(basic_reduce_form(*i));
+		      }
+		  }
+		else if (bo)
+		  {
+		    if (bo->op() == binop::U)
+		      {
+			// (a U b) | (a U c) = a U (b | c)
+			ftmp = bo->first();
 			tmpUright = new multop::vec;
 			for (multop::vec::iterator j = i; j != res->end(); j++)
 			  {
 			    if (!*j)
 			      continue;
-			    if (node_type(*j) == node_type_form_visitor::Binop
-				&& dynamic_cast<binop*>(*j)->op() == binop::U
-				&& ftmp == dynamic_cast<binop*>(*j)->first())
+			    binop* bo2 = dynamic_cast<binop*>(*j);
+			    if (bo2 && bo2->op() == binop::U
+				&& ftmp == bo2->first())
 			      {
-				bo = dynamic_cast<binop*>(*j);
 				tmpUright
-				  ->push_back(basic_reduce_form(bo->second()));
+				  ->push_back(basic_reduce_form(bo2->second()));
 				if (j != i)
 				  {
 				    destroy(*j);
@@ -537,23 +521,20 @@ namespace spot
 							multop::
 							instance(multop::Or,
 								 tmpUright)));
-			break;
 		      }
-
-		    // (a R b) | (c R b) = (a | c) R b
-		    if (dynamic_cast<binop*>(*i)->op() == binop::R)
+		    else if (bo->op() == binop::R)
 		      {
+			// (a R b) | (c R b) = (a | c) R b
 			ftmp = dynamic_cast<binop*>(*i)->second();
 			tmpRright = new multop::vec;
 			for (multop::vec::iterator j = i; j != res->end(); j++)
 			  {
 			    if (!*j)
 			      continue;
-			    if (node_type(*j) == node_type_form_visitor::Binop
-				&& dynamic_cast<binop*>(*j)->op() == binop::R
-				&& ftmp == dynamic_cast<binop*>(*j)->second())
+			    binop* bo2 = dynamic_cast<binop*>(*j);
+			    if (bo2 && bo2->op() == binop::R
+				&& ftmp == bo2->second())
 			      {
-				bo = dynamic_cast<binop*>(*j);
 				tmpRright
 				  ->push_back(basic_reduce_form(bo->first()));
 				if (j != i)
@@ -569,40 +550,44 @@ namespace spot
 						      instance(multop::Or,
 							       tmpRright),
 						      basic_reduce_form(ftmp)));
-			break;
 		      }
+		    else
+		      {
+			tmpOther->push_back(basic_reduce_form(*i));
+		      }
+		  }
+		else
+		  {
 		    tmpOther->push_back(basic_reduce_form(*i));
-		    break;
-		  default:
-		    tmpOther->push_back(basic_reduce_form(*i));
-		    break;
 		  }
 		destroy(*i);
 	      }
 
-	    delete(tmpFG);
-	    tmpFG = NULL;
+	    delete tmpFG;
+	    tmpFG = 0;
 
 	    break;
 	  }
 
-
 	res->clear();
-	delete(res);
+	delete res;
 
 	if (tmpX->size())
 	  tmpOther->push_back(unop::instance(unop::X,
 					     multop::instance(mo->op(),
 							      tmpX)));
-	else delete(tmpX);
+	else
+	  delete tmpX;
 
 	if (tmpU->size())
 	  tmpOther->push_back(multop::instance(mo->op(), tmpU));
-	else delete(tmpU);
+	else
+	  delete tmpU;
 
 	if (tmpR->size())
 	  tmpOther->push_back(multop::instance(mo->op(), tmpR));
-	else delete(tmpR);
+	else
+	  delete tmpR;
 
 	if ((tmpGF != NULL) &&
 	    (tmpGF->size()))
diff --git a/src/ltlvisit/forminf.cc b/src/ltlvisit/forminf.cc
index 81633999b..5589cf739 100644
--- a/src/ltlvisit/forminf.cc
+++ b/src/ltlvisit/forminf.cc
@@ -58,53 +58,6 @@ namespace spot
       return false;
     }
 
-    node_type_form_visitor::node_type_form_visitor(){}
-
-    node_type_form_visitor::type
-    node_type_form_visitor::result() const
-    {
-      return result_;
-    }
-
-    void
-    node_type_form_visitor::visit(const atomic_prop*)
-    {
-      result_ = node_type_form_visitor::Atom;
-    }
-
-    void
-    node_type_form_visitor::visit(const constant*)
-    {
-      result_ = node_type_form_visitor::Const;
-    }
-
-    void
-    node_type_form_visitor::visit(const unop*)
-    {
-      result_ = node_type_form_visitor::Unop;
-    }
-
-    void
-    node_type_form_visitor::visit(const binop*)
-    {
-      result_ = node_type_form_visitor::Binop;
-    }
-
-    void
-    node_type_form_visitor::visit(const multop*)
-    {
-      result_ = node_type_form_visitor::Multop;
-    }
-
-    node_type_form_visitor::type
-    node_type(const formula* f)
-    {
-      node_type_form_visitor v;
-      assert(f != NULL);
-      const_cast<formula*>(f)->accept(v);
-      return v.result();
-    }
-
     class form_eventual_universal_visitor : public const_visitor
     {
     public:
@@ -578,7 +531,8 @@ namespace spot
       return false;
     }
 
-    bool infneg_form(const formula* f1, const formula* f2, int n)
+    bool
+    infneg_form(const formula* f1, const formula* f2, int n)
     {
       const formula* ftmp1;
       const formula* ftmp2;
diff --git a/src/ltlvisit/reducform.cc b/src/ltlvisit/reducform.cc
index ed15ae029..856fe46f8 100644
--- a/src/ltlvisit/reducform.cc
+++ b/src/ltlvisit/reducform.cc
@@ -144,14 +144,15 @@ namespace spot
 		    return;
 		  }
 		/* a < b => a U (b U c) = (b U c) */
-		if (node_type(f2) == node_type_form_visitor::Binop
-		    && dynamic_cast<binop*>(f2)->op() == binop::U
-		    && inf_form(f1, dynamic_cast<binop*>(f2)->first()))
-		  {
-		    result_ = f2;
-		    destroy(f1);
-		    return;
-		  }
+		{
+		  binop* bo = dynamic_cast<binop*>(f2);
+		  if (bo && bo->op() == binop::U && inf_form(f1, bo->first()))
+		    {
+		      result_ = f2;
+		      destroy(f1);
+		      return;
+		    }
+		}
 		break;
 
 	      case binop::R:
@@ -170,16 +171,16 @@ namespace spot
 		    return;
 		  }
 		/* b < a => a R (b R c) = b R c */
-		if (node_type(f2) == node_type_form_visitor::Binop
-		    && dynamic_cast<binop*>(f2)->op() == binop::R
-		    && inf_form(dynamic_cast<binop*>(f2)->first(), f1))
-		  {
-		    result_ = f2;
-		    destroy(f1);
-		    return;
-		  }
+		{
+		  binop* bo = dynamic_cast<binop*>(f2);
+		  if (bo && bo->op() == binop::R && inf_form(bo->first(), f1))
+		    {
+		      result_ = f2;
+		      destroy(f1);
+		      return;
+		    }
+		}
 		break;
-
 	      }
 	  }
 	result_ = binop::instance(bo->op(), f1, f2);
diff --git a/src/ltlvisit/reducform.hh b/src/ltlvisit/reducform.hh
index 8c4ff2217..2fd5a7245 100644
--- a/src/ltlvisit/reducform.hh
+++ b/src/ltlvisit/reducform.hh
@@ -74,24 +74,6 @@ namespace spot
     /// FIXME: Describe what universal formulae are.  Cite paper.
     bool is_universal(const formula* f);
 
-    /// Type the first node of a formula.
-    class node_type_form_visitor : public const_visitor
-    {
-    public:
-      enum type { Atom, Const, Unop, Binop, Multop };
-      node_type_form_visitor();
-      virtual ~node_type_form_visitor(){};
-      type result() const;
-      void visit(const atomic_prop* ap);
-      void visit(const constant* c);
-      void visit(const unop* uo);
-      void visit(const binop* bo);
-      void visit(const multop* mo);
-    protected:
-      type result_;
-    };
-    node_type_form_visitor::type node_type(const formula* f);
-
     /// Whether a formula starts with GF.
     bool is_GF(const formula* f);
     /// Whether a formula starts with FG.
diff --git a/src/sanity/style.test b/src/sanity/style.test
index 5a57c53ce..1b54d4cd6 100755
--- a/src/sanity/style.test
+++ b/src/sanity/style.test
@@ -44,6 +44,9 @@ for dir in "${INCDIR-..}" "${INCDIR-..}"/../iface; do
     grep '[	 ]if (.*).*;' $tmp &&
       diag 'if body should be on another line.'
 
+    grep '[	 ]else.*;' $tmp &&
+      diag 'else body should be on another line.'
+
     grep '[	 ]while(' $tmp &&
       diag 'Missing space after "while"'
 
@@ -104,6 +107,12 @@ for dir in "${INCDIR-..}" "${INCDIR-..}"/../iface; do
     grep '{.*{' $tmp &&
       diag 'No two { on the same line.'
 
+    grep -e 'delete[	 ]*[(][^(]*[)];' $tmp &&
+      diag 'No useless parentheses after delete.'
+
+    grep -e 'return[	 ]*[(][^(]*[)];' $tmp &&
+      diag 'No useless parentheses after delete.'
+
     $fail && echo "$file" >>failures
   done
 done