Added peg::udl for 'tag' user defined literal.

Author: yhirose

language/culebra/culebra.h

@@ -547,7 +547,7 @@ struct Interpreter
     }
 
     Value eval(const peg::Ast& ast, std::shared_ptr<Environment> env) {
-        using peg::operator"" _;
+        using namespace peg::udl;
 
         if (debugger_) {
             if (ast.original_tag == "STATEMENT"_) {
@@ -715,7 +715,7 @@ struct Interpreter
     }
 
     Value eval_call(const peg::Ast& ast, std::shared_ptr<Environment> env) {
-        using peg::operator"" _;
+        using namespace peg::udl;
 
         Value val = eval(*ast.nodes[0], env);
 
@@ -836,7 +836,7 @@ struct Interpreter
             }
             return rval;
         } else {
-            using peg::operator"" _;
+            using namespace peg::udl;
 
             Value lval = eval(*ast.nodes[lvaloff], env);
 

language/culebra/main.cc

@@ -6,6 +6,7 @@
 #include <vector>
 
 using namespace peg;
+using namespace peg::udl;
 using namespace std;
 
 bool read_file(const char* path, vector<char>& buff)

language/pl0/pl0.cc

@@ -11,6 +11,7 @@
 #include <sstream>
 
 using namespace peg;
+using namespace peg::udl;
 using namespace std;
 
 /*

peglib.h

@@ -2151,9 +2151,11 @@ inline constexpr unsigned int str2tag(const char* str, int h = 0) {
     return !str[h] ? 5381 : (str2tag(str, h + 1) * 33) ^ static_cast<unsigned char>(str[h]);
 }
 
+namespace udl {
 inline constexpr unsigned int operator "" _(const char* s, size_t) {
     return str2tag(s);
 }
+}
 #endif
 
 template <typename Annotation>