[4088] Bison example integrated.

1 files changed, 45 insertions, 0 deletions

diff --git a/src/lib/eval/eval_context.h b/src/lib/eval/eval_context.h
new file mode 100644
index 0000000000..1d26f04faa
--- /dev/null
+++ b/src/lib/eval/eval_context.h
@@ -0,0 +1,45 @@
+#ifndef CALCXX_DRIVER_HH
+# define CALCXX_DRIVER_HH
+# include <string>
+# include <map>
+# include "parser.h"
+
+// Tell Flex the lexer's prototype ...
+# define YY_DECL \
+  yy::calcxx_parser::symbol_type yylex (calcxx_driver& driver)
+
+// ... and declare it for the parser's sake.
+YY_DECL;
+
+// Conducting the whole scanning and parsing of Calc++.
+class calcxx_driver
+{
+public:
+  calcxx_driver ();
+  virtual ~calcxx_driver ();
+
+  std::map<std::string, int> variables;
+
+  int result;
+
+  // Handling the scanner.
+  void scan_begin ();
+  void scan_end ();
+  bool trace_scanning;
+
+  // Run the parser on file F.
+  // Return 0 on success.
+  int parse (const std::string& f);
+
+  // The name of the file being parsed.
+  // Used later to pass the file name to the location tracker.
+
+  std::string file;
+  // Whether parser traces should be generated.
+  bool trace_parsing;
+
+  // Error handling.
+  void error (const yy::location& l, const std::string& m);
+  void error (const std::string& m);
+};
+#endif // ! CALCXX_DRIVER_HH