upd

qic.c

@@ -414,21 +414,27 @@ int is_required(char *path) {
   return 0;
 }
 
-void traverse(char *source, size_t pos, size_t *line, size_t *col) {
+char *traverse(char *source, size_t pos, size_t *line, size_t *col) {
   *line = 1;
   *col = 1;
 
+  size_t p = 0;
+
   for (size_t i = 0; i < pos; i++) {
      if (source[i] == '\n') {
        (*line)++;
        (*col) = 1;
+
+       p = i;
      } else (*col)++;
   }
+
+  return &source[p];
 }
 
 void format_error(char *filename, char *source, size_t pos, char *fmt, ...) {
   size_t line, col;
-  traverse(source, pos, &line, &col);
+  char *src = traverse(source, pos, &line, &col);
 
   va_list args;
   va_start(args, fmt);
@@ -438,6 +444,22 @@ void format_error(char *filename, char *source, size_t pos, char *fmt, ...) {
   fputc('\n', stderr);
 
   va_end(args);
+
+  if (!*src)
+    return;
+
+  fputc('\t', stderr);
+
+  for (size_t i = 0; src[i] && src[i] != '\n' && i < 64; i++)
+    fputc(src[i], stderr);
+
+  fputc('\n', stderr);
+  fputc('\t', stderr);
+
+  for (size_t i = 0; i < col && i < 64; i++)
+    fputc(' ', stderr);
+
+  fputs("^\n", stderr);
 }
 
 #define GETFNAME(fi) ((char *)((list_t *)list_index(FILES, fi))->data[0])
@@ -1223,7 +1245,15 @@ node_t *parse_primary(list_t *tokens, size_t *pos) {
   } else if (MATCH(NUMBER) || MATCH(STRING) || MATCH(FSTRING) || MATCH(NAME))
     return NODET(LITERAL, tokens->data[(*pos)-1]);
 
-  PARSE_ERROR("expected expression");
+  if (AT(RPAR)) {
+    PARSE_ERROR("extraneous )");
+  } else if (AT(RSB)) {
+    PARSE_ERROR("extraneous ]");
+  } else if (AT(RCB)) {
+    PARSE_ERROR("extraneous }");
+  } else {
+    PARSE_ERROR("expected expression");
+  }
 
   return NULL;
 }
@@ -3514,7 +3544,6 @@ void compile_node(buffer_t *gbuf, buffer_t *buf, list_t *ctx, table_t *ltab, sta
 
           buffer_t *tbuf = buffer_new();
 
-
           for (size_t i = 0; i < strlen(text); i++) {
             char c = text[i];
             if (c == '$' && text[i+1] == '$') {
@@ -3548,7 +3577,14 @@ void compile_node(buffer_t *gbuf, buffer_t *buf, list_t *ctx, table_t *ltab, sta
               char *source = buffer_read(tbuf2);
 
               list_t *pair = list_new();
-              list_push(pair, "<fstring>");
+
+              buffer_t *fname = buffer_new();
+              size_t line, col;
+              (void)traverse(GETSRC(-1), node->pos, &line, &col);
+
+              buffer_fmt(fname, "<fstring at %s:%zu:%zu>", GETFNAME(-1), line, col);
+
+              list_push(pair, buffer_read(fname));
               list_push(pair, source);
 
               list_push(FILES, pair);