Re: Public / protected access to parser's symbol_name() in C++

[Akim Demaille]

> Le 10 mai 2020 à 09:57, Akim Demaille <a...@lrde.epita.fr> a écrit :
> 
> I'm installing this.

I should have specified that I'll install it in the 'maint' branch,
to become 3.6.1 soon.

I'm also installing this in maint.  I don't like to add new features
in bug fix releases, but now having this was really a bug in the API.

commit bf98d94f4f1cce09671160cce22774c09d089cd0
Author: Akim Demaille <akim.demai...@gmail.com>
Date:   Sun May 10 09:58:30 2020 +0200

    c++: provide yy::parser::symbol_type::name
    
    * data/skeletons/c++.m4 (yy::parser::basic_symbol::name): New.
    * data/skeletons/lalr1.cc (yy_print_): Use it.
    * doc/bison.texi: Document.
    * tests/c++.at: Check.

diff --git a/NEWS b/NEWS
index 509766f7..b229e169 100644
--- a/NEWS
+++ b/NEWS
@@ -8,6 +8,10 @@ GNU Bison NEWS
 
   In C++, yy::parser::symbol_name is now a public member, as was intended.
 
+** New features
+
+  In C++, yy::parser::symbol_type now has a public name() member function.
+
 * Noteworthy changes in release 3.6 (2020-05-08) [stable]
 
 ** Backward incompatible changes
diff --git a/data/skeletons/c++.m4 b/data/skeletons/c++.m4
index 7ce45078..b862bf3c 100644
--- a/data/skeletons/c++.m4
+++ b/data/skeletons/c++.m4
@@ -357,6 +357,29 @@ m4_define([b4_symbol_type_define],
         Base::clear ();
       }
 
+]b4_parse_error_bmatch(
+[custom\|detailed],
+[[      /// The user-facing name of this symbol.
+      const char *name () const YY_NOEXCEPT
+      {
+        return ]b4_parser_class[::symbol_name (this->kind ());
+      }]],
+[simple],
+[[#if ]b4_api_PREFIX[DEBUG || ]b4_token_table_flag[
+      /// The user-facing name of this symbol.
+      const char *name () const YY_NOEXCEPT
+      {
+        return ]b4_parser_class[::symbol_name (this->kind ());
+      }
+#endif // #if ]b4_api_PREFIX[DEBUG || ]b4_token_table_flag[
+]],
+[verbose],
+[[      /// The user-facing name of this symbol.
+      std::string name () const YY_NOEXCEPT
+      {
+        return ]b4_parser_class[::symbol_name (this->kind ());
+      }]])[
+
       /// Backward compatibility (Bison 3.6).
       symbol_kind_type type_get () const YY_NOEXCEPT;
 
diff --git a/data/skeletons/lalr1.cc b/data/skeletons/lalr1.cc
index 6fa5674e..2c4b17c0 100644
--- a/data/skeletons/lalr1.cc
+++ b/data/skeletons/lalr1.cc
@@ -256,8 +256,7 @@ m4_define([b4_shared_declarations],
 [verbose],
 [[    /// The user-facing name of the symbol whose (internal) number is
     /// YYSYMBOL.  No bounds checking.
-    static std::string symbol_name (symbol_kind_type yysymbol);
-]])[
+    static std::string symbol_name (symbol_kind_type yysymbol);]])[
 
 ]b4_token_constructor_define[
 ]b4_parse_error_bmatch([custom\|detailed\|verbose], [[
@@ -822,7 +821,7 @@ m4_if(b4_prefix, [yy], [],
       {
         symbol_kind_type yykind = yysym.kind ();
         yyo << (yykind < YYNTOKENS ? "token" : "nterm")
-            << ' ' << symbol_name (yykind) << " ("]b4_locations_if([
+            << ' ' << yysym.name () << " ("]b4_locations_if([
             << yysym.location << ": "])[;
         ]b4_symbol_actions([printer])[
         yyo << ')';
diff --git a/doc/bison.texi b/doc/bison.texi
index 7e51633b..726cbf22 100644
--- a/doc/bison.texi
+++ b/doc/bison.texi
@@ -12154,6 +12154,8 @@ values, which is always less than @code{YYNTOKENS}.
 
 @deftypemethod {parser} {const char *} symbol_name (@code{symbol_kind_t} 
@var{symbol}) @code{const}
 The name of the symbol whose kind is @var{symbol}, possibly translated.
+
+Returns a @code{std::string} when @code{parse.error} is @code{verbose}.
 @end deftypemethod
 
 A custom syntax error function looks as follows.  This implementation is
@@ -12286,6 +12288,12 @@ applicable) location.
 The kind of this symbol.
 @end deftypemethod
 
+@deftypemethod {symbol_type} {const char *} name () @code{const}
+The name of the kind of this symbol.
+
+Returns a @code{std::string} when @code{parse.error} is @code{verbose}.
+@end deftypemethod
+
 @sp 1
 
 For each token kind, Bison generates named constructors as follows.
diff --git a/tests/c++.at b/tests/c++.at
index d3f52513..5789c8b0 100644
--- a/tests/c++.at
+++ b/tests/c++.at
@@ -162,6 +162,7 @@ int main()
     parser::symbol_type s = parser::make_INT (12);
     assert_eq (s.kind (), parser::symbol_kind::S_INT);
     assert_eq (parser::symbol_name (s.kind ()), "\"int\"");
+    assert_eq (s.name (), "\"int\"");
     assert_eq (s.value.as<int> (), 12);
   }