add initial empty C, flex, and bison sources

src/parser/parser.h

@@ -0,0 +1,4 @@
+#ifndef PARSER_H
+#define PARSER_H
+
+#endif

src/parser/parser.l

@@ -0,0 +1,15 @@
+%option nounput
+%option bison-locations
+
+%{
+
+#include "parser.h"
+#include "parser.tab.h"
+
+%}
+
+%x str
+
+%%
+
+%%

src/parser/parser.y

@@ -0,0 +1,38 @@
+%{
+
+#include <stdio.h>
+#include "parser.h"
+#include "parser.tab.h"
+
+#define yyerror(msg) handle_error(msg, &yyloc)
+
+int yylex(YYSTYPE *, YYLTYPE *);
+static void handle_error(const char * str, const YYLTYPE * yylloc);
+
+%}
+
+%pure-parser
+%locations
+%error-verbose
+
+%token PLUS;
+%token MINUS;
+
+%%
+
+translation_unit: PLUS;
+
+%%
+
+static void handle_error(const char * str, const YYLTYPE * yylloc)
+{
+    fprintf(stderr, "error: %s (line %d, column %d)\n",
+            str,
+            yylloc->first_line,
+            yylloc->first_column);
+}
+
+int yywrap(void)
+{
+    return 1;
+}