acc_cond: rename is_tt/is_ff as is_t/is_f and add printer

* spot/twa/acc.cc, spot/twa/acc.hh: Here.
* spot/parseaut/parseaut.yy, spot/twa/acc.hh,
spot/twaalgos/gtec/gtec.cc, spot/twaalgos/hoa.cc,
spot/twaalgos/neverclaim.cc, spot/twaalgos/product.cc,
spot/twaalgos/remfin.cc, spot/twaalgos/strength.cc: Adjust.
* NEWS: Mention the changes.
* wrap/python/spot_impl.i: Bind acc_cond the printer.
* wrap/python/tests/acc_cond.ipynb: Add more examples.

spot/parseaut/parseaut.yy

@@ -572,7 +572,7 @@ header-item: "States:" INT
 	       res.ignore_more_acc = true;
 	       // Not setting the acceptance in case of error will
 	       // force it to be true.
-	       if (res.opts.want_kripke && (!$4->is_tt() || $2 > 0))
+	       if (res.opts.want_kripke && (!$4->is_t() || $2 > 0))
 		 error(@2 + @4,
 		       "the acceptance for Kripke structure must be '0 t'");
 	       else

spot/twa/acc.cc

@@ -51,6 +51,11 @@ namespace spot
     return os;
   }
 
+  std::ostream& operator<<(std::ostream& os, const acc_cond& acc)
+  {
+    return os << '(' << acc.num_sets() << ", " << acc.get_acceptance() << ')';
+  }
+
   namespace
   {
     void default_set_printer(std::ostream& os, int v)
@@ -411,9 +416,9 @@ namespace spot
 
   int acc_cond::is_rabin() const
   {
-    if (code_.is_ff())
+    if (code_.is_f())
       return num_ == 0 ? 0 : -1;
-    if ((num_ & 1) || code_.is_tt())
+    if ((num_ & 1) || code_.is_t())
       return -1;
 
     if (is_rs(code_, acc_op::Or, acc_op::And, all_sets()))
@@ -424,9 +429,9 @@ namespace spot
 
   int acc_cond::is_streett() const
   {
-    if (code_.is_tt())
+    if (code_.is_t())
       return num_ == 0 ? 0 : -1;
-    if ((num_ & 1) || code_.is_ff())
+    if ((num_ & 1) || code_.is_f())
       return -1;
 
     if (is_rs(code_, acc_op::And, acc_op::Or, all_sets()))
@@ -444,7 +449,7 @@ namespace spot
 	pairs.resize(num_);
 	return true;
       }
-    if (code_.is_tt()
+    if (code_.is_t()
 	|| code_.back().op != acc_op::Or)
       return false;
 
@@ -670,7 +675,7 @@ namespace spot
     if (sets == 0)
       {
 	max = true;
-	odd = is_tt();
+	odd = is_t();
 	return true;
       }
     acc_cond::mark_t u_inf;
@@ -857,7 +862,7 @@ namespace spot
   std::pair<bool, acc_cond::mark_t>
   acc_cond::unsat_mark() const
   {
-    if (is_tt())
+    if (is_t())
       return {false, 0U};
     if (!uses_fin_acceptance())
       return {true, 0U};
@@ -1105,7 +1110,7 @@ namespace spot
 
   acc_cond::acc_code acc_cond::acc_code::complement() const
   {
-    if (is_tt())
+    if (is_t())
       return acc_cond::acc_code::f();
     return complement_rec(&back());
   }
@@ -1165,7 +1170,7 @@ namespace spot
   acc_cond::acc_code
   acc_cond::acc_code::strip(acc_cond::mark_t rem, bool missing) const
   {
-    if (is_tt() || is_ff())
+    if (is_t() || is_f())
       return *this;
     return strip_rec(&back(), rem, missing);
   }
@@ -1173,7 +1178,7 @@ namespace spot
   acc_cond::mark_t
   acc_cond::acc_code::used_sets() const
   {
-    if (is_tt() || is_ff())
+    if (is_t() || is_f())
       return 0U;
     acc_cond::mark_t used_in_cond = 0U;
     auto pos = &back();
@@ -1201,7 +1206,7 @@ namespace spot
   std::pair<acc_cond::mark_t, acc_cond::mark_t>
   acc_cond::acc_code::used_inf_fin_sets() const
   {
-    if (is_tt() || is_ff())
+    if (is_t() || is_f())
       return {0U, 0U};
 
     acc_cond::mark_t used_fin = 0U;

spot/twa/acc.hh

@@ -395,14 +395,14 @@ namespace spot
 	return !(*this == other);
       }
 
-      bool is_tt() const
+      bool is_t() const
       {
 	unsigned s = size();
 	return s == 0
 	  || ((*this)[s - 1].op == acc_op::Inf && (*this)[s - 2].mark == 0U);
       }
 
-      bool is_ff() const
+      bool is_f() const
       {
 	unsigned s = size();
 	return s > 1
@@ -557,12 +557,12 @@ namespace spot
 
       acc_code& operator&=(acc_code&& r)
       {
-	if (is_tt() || r.is_ff())
+	if (is_t() || r.is_f())
 	  {
 	    *this = std::move(r);
 	    return *this;
 	  }
-	if (is_ff() || r.is_tt())
+	if (is_f() || r.is_t())
 	  return *this;
 	unsigned s = size() - 1;
 	unsigned rs = r.size() - 1;
@@ -649,12 +649,12 @@ namespace spot
 
       acc_code& operator&=(const acc_code& r)
       {
-	if (is_tt() || r.is_ff())
+	if (is_t() || r.is_f())
 	  {
 	    *this = r;
 	    return *this;
 	  }
-	if (is_ff() || r.is_tt())
+	if (is_f() || r.is_t())
 	  return *this;
 	unsigned s = size() - 1;
 	unsigned rs = r.size() - 1;
@@ -754,9 +754,9 @@ namespace spot
 
       acc_code& operator|=(acc_code&& r)
       {
-	if (is_tt() || r.is_ff())
+	if (is_t() || r.is_f())
 	  return *this;
-	if (is_ff() || r.is_tt())
+	if (is_f() || r.is_t())
 	  {
 	    *this = std::move(r);
 	    return *this;
@@ -930,14 +930,24 @@ namespace spot
       return uses_fin_acceptance_;
     }
 
-    bool is_tt() const
+    bool is_t() const
     {
-      return code_.is_tt();
+      return code_.is_t();
     }
 
-    bool is_ff() const
+    bool is_all() const
     {
-      return code_.is_ff();
+      return num_ == 0 && is_t();
+    }
+
+    bool is_f() const
+    {
+      return code_.is_f();
+    }
+
+    bool is_none() const
+    {
+      return num_ == 0 && is_f();
     }
 
     bool is_buchi() const
@@ -1158,6 +1168,7 @@ namespace spot
     mark_t::value_t all_;
     acc_code code_;
     bool uses_fin_acceptance_ = false;
+
   };
 
   /// \brief Parse a string into an acc_code
@@ -1179,6 +1190,9 @@ namespace spot
   ///
   /// A spot::parse_error is thrown on syntax error.
   SPOT_API acc_cond::acc_code parse_acc_code(const char* input);
+
+  SPOT_API
+  std::ostream& operator<<(std::ostream& os, const acc_cond& acc);
 }
 
 namespace std

spot/twaalgos/gtec/gtec.cc

@@ -133,7 +133,7 @@ namespace spot
   {
     {
       auto acc = ecs_->aut->acc();
-      if (acc.get_acceptance().is_ff())
+      if (acc.get_acceptance().is_f())
 	return nullptr;
       if (acc.uses_fin_acceptance())
 	throw std::runtime_error
@@ -395,7 +395,7 @@ namespace spot
   {
     {
       auto acc = ecs_->aut->acc();
-      if (acc.get_acceptance().is_ff())
+      if (acc.get_acceptance().is_f())
 	return nullptr;
       if (acc.uses_fin_acceptance())
 	throw std::runtime_error

spot/twaalgos/hoa.cc

@@ -313,7 +313,7 @@ namespace spot
     acc_cond::acc_code acc_c = aut->acc().get_acceptance();
     if (aut->acc().is_generalized_buchi())
       {
-	if (aut->acc().is_tt())
+	if (aut->acc().is_all())
 	  os << "acc-name: all";
 	else if (aut->acc().is_buchi())
 	  os << "acc-name: Buchi";
@@ -323,7 +323,7 @@ namespace spot
       }
     else if (aut->acc().is_generalized_co_buchi())
       {
-	if (aut->acc().is_ff())
+	if (aut->acc().is_none())
 	  os << "acc-name: none";
 	else if (aut->acc().is_co_buchi())
 	  os << "acc-name: co-Buchi";

spot/twaalgos/neverclaim.cc

@@ -205,7 +205,7 @@ namespace spot
   print_never_claim(std::ostream& os, const const_twa_ptr& g,
 			const char* options)
   {
-    if (!(g->acc().is_buchi() || g->acc().is_tt()))
+    if (!(g->acc().is_buchi() || g->acc().is_all()))
       throw std::runtime_error
 	("Never claim output only supports Büchi acceptance");
     never_claim_output d(os, options);

spot/twaalgos/product.cc

@@ -80,7 +80,7 @@ namespace spot
 	};
 
       res->set_init_state(new_state(left_state, right_state));
-      if (right_acc.is_ff())
+      if (right_acc.is_f())
 	// Do not bother doing any work if the resulting acceptance is
 	// false.
 	return res;

spot/twaalgos/remfin.cc

@@ -312,7 +312,7 @@ namespace spot
 
       auto code = aut->get_acceptance();
 
-      if (code.is_tt())
+      if (code.is_t())
 	return nullptr;
 
       acc_cond::mark_t inf_pairs = 0U;
@@ -640,7 +640,7 @@ namespace spot
 	  auto c = acc.inf(m);
 	  for (unsigned i = 0; i < sz; ++i)
 	    {
-	      if (!code[i].is_tt())
+	      if (!code[i].is_t())
 		continue;
 	      add[i] = m;
 	      code[i] &= std::move(c);

spot/twaalgos/strength.cc

@@ -126,7 +126,7 @@ namespace spot
 
   bool is_safety_mwdba(const const_twa_graph_ptr& aut)
   {
-    if (!(aut->acc().is_buchi() || aut->acc().is_tt()))
+    if (!(aut->acc().is_buchi() || aut->acc().is_all()))
       throw std::runtime_error
 	("is_safety_mwdba() should be called on a Buchi automaton");