Add some preprocessor magic

main.c

@@ -14,25 +14,36 @@ F ::= (E)|i
 
 
 #define eprintf(...) fprintf(stderr, __VA_ARGS__)
+#define fatal(...) { eprintf(__VA_ARGS__); putc('\n', stderr); exit(1); }
+#define ENUM(x) x,
+#define STR(x) #x,
 
 
+#define __TokenType(f) \
+    f(EMPTY) \
+    f(INTEGER) \
+    f(PLUS) \
+    f(MULT) \
+    f(LBRACE) \
+    f(RBRACE) \
+    f(LF) \
+    f(EF) \
+
 typedef enum TokenType {
-    INTEGER      =  1,
-    PLUS         =  2,
-    MULT         =  4,
-    LBRACE       =  8,
-    RBRACE       = 16,
-    LF           = 32,
-    EF           = 64,
+    __TokenType(ENUM)
 } TokenType;
 
+const char *TokenTypeStr[] = {
+    __TokenType(STR)
+};
+
+
 typedef struct _Token {
     TokenType type;
     int value;
 } Token;
 
 
-void fatal(const char* message);
 Token scan();
 
 int e();
@@ -90,8 +101,7 @@ Token scan() {
         token.type = LF; break;
     case EOF: token.type = EF; break;
     default:
-        eprintf("'%c' (%d)\n", s, s);
-        fatal("Unexpected symbol");
+        fatal("Unexpected symbol: '%c' (%X)", s, s);
         break;
     }
     return token;
@@ -134,13 +144,8 @@ int f() {
         fatal("Unexpected EOF");
     }
     else {
-        fatal("Unexpected token");
+        fatal("Unexpected token: %s (%d)", TokenTypeStr[current.type], current.type);
     }
     current = scan();
     return result;
 }
-
-void fatal(const char* message) {
-    eprintf("Error: %s\n", message);
-    exit(1);
-}