C++--11 requires to support both > > and >> to close

 nested template arguments

git-svn-id: svn+ssh://svn.cprover.org/srv/svn/cbmc/trunk@6098 6afb6bc1-c8e4-404c-8f48-9ae832c5b171

Author: kroening

src/cpp/cpp_token.h

@@ -21,7 +21,6 @@ class cpp_tokent
   std::string text;
   unsigned line_no;
   irep_idt filename;
-  unsigned pos;
 
   void clear()
   {
@@ -30,7 +29,6 @@ class cpp_tokent
     text="";
     line_no=0;
     filename="";
-    pos=0;
   }
 
   void swap(cpp_tokent &token)
@@ -40,7 +38,6 @@ class cpp_tokent
     text.swap(token.text);
     std::swap(line_no, token.line_no);
     filename.swap(token.filename);
-    std::swap(pos, token.pos);    
   }
 };
 

src/cpp/cpp_token_buffer.cpp

@@ -148,7 +148,6 @@ void cpp_token_buffert::read_token()
   //std::cout << "TOKEN: " << kind << " " << tokens.back().text << std::endl;
 
   tokens.back().kind=kind;
-  tokens.back().pos=token_vector.size()-1;
 
   //std::cout << "II: " << token_vector.back()->kind << std::endl;
   //std::cout << "I2: " << token_vector.size() << std::endl;
@@ -187,3 +186,46 @@ void cpp_token_buffert::Restore(post pos)
 {
   current_pos=pos;
 }
+
+/*******************************************************************\
+
+Function: cpp_token_buffert::Replace
+
+  Inputs:
+
+ Outputs:
+
+ Purpose:
+
+\*******************************************************************/
+
+void cpp_token_buffert::Replace(const cpp_tokent &token)
+{
+  assert(current_pos<=token_vector.size());
+
+  if(token_vector.size()==current_pos) read_token();
+
+  *token_vector[current_pos]=token;
+}
+
+/*******************************************************************\
+
+Function: cpp_token_buffert::Replace
+
+  Inputs:
+
+ Outputs:
+
+ Purpose:
+
+\*******************************************************************/
+
+void cpp_token_buffert::Insert(const cpp_tokent &token)
+{
+  assert(current_pos<=token_vector.size());
+
+  tokens.push_back(token);
+
+  token_vector.insert(token_vector.begin()+current_pos,
+                      --tokens.end());
+}

src/cpp/cpp_token_buffer.h

@@ -27,6 +27,8 @@ class cpp_token_buffert
 
   post Save();
   void Restore(post pos);
+  void Replace(const cpp_tokent &token);
+  void Insert(const cpp_tokent &token);
 
   void clear()
   {

src/cpp/parse.cpp

@@ -4208,8 +4208,11 @@ bool Parser::rTemplateArgs(irept &template_args)
 
     // try type name first
     if(rTypeNameOrFunctionType(a) &&
-       ((lex.LookAhead(0) == '>' || lex.LookAhead(0) == ',') ||
-        (lex.LookAhead(0)==TOK_ELLIPSIS && lex.LookAhead(1) == '>'))
+       ((lex.LookAhead(0) == '>' || lex.LookAhead(0) == ',' ||
+         lex.LookAhead(0)==TOK_SHIFTRIGHT) ||
+        (lex.LookAhead(0)==TOK_ELLIPSIS &&
+         (lex.LookAhead(1) == '>' ||
+          lex.LookAhead(1)==TOK_SHIFTRIGHT)))
         )
     {
       #ifdef DEBUG
@@ -4270,6 +4273,7 @@ bool Parser::rTemplateArgs(irept &template_args)
     template_args.get_sub().push_back(irept(irep_idt()));
     template_args.get_sub().back().swap(exp);
 
+    pos=lex.Save();
     cpp_tokent tk2;
     switch(lex.get_token(tk2))
     {
@@ -4280,13 +4284,14 @@ bool Parser::rTemplateArgs(irept &template_args)
       break;
 
     case TOK_SHIFTRIGHT: // turn >> into > >
-      // the newer C++ standards frown on this!
-
-      // turn >> into > > // TODO
-      //lex.GetOnlyClosingBracket(tk2);
-      //temp_args=Ptree::List(new Leaf(tk1), args,
-      //                      new Leaf(tk2.ptr, 1));
-      return false;
+      lex.Restore(pos);
+      tk2.kind='>';
+      tk2.text='>';
+      lex.Replace(tk2);
+      lex.Insert(tk2);
+      assert(lex.LookAhead(0)=='>');
+      assert(lex.LookAhead(1)=='>');
+      return true;
 
     default:
       return false;
@@ -7902,6 +7907,8 @@ bool Parser::maybeTemplateArgs()
       }
       else if(u=='\0' || u==';' || u=='}')
         return false;
+      else if(u==TOK_SHIFTRIGHT && n>=2)
+        n-=2;
 
       #ifdef DEBUG
       std::cout << std::string(__indent, ' ') << "Parser::maybeTemplateArgs 4\n";