diff --git a/include/fmt/format.h b/include/fmt/format.h
index f101c913..e4f7633d 100644
--- a/include/fmt/format.h
+++ b/include/fmt/format.h
@@ -2328,16 +2328,22 @@ FMT_CONSTEXPR const Char* parse_arg_id(const Char* begin, const Char* end,
                                        IDHandler&& handler) {
   FMT_ASSERT(begin != end, "");
   Char c = *begin;
-  if (c == '}' || c == ':') return handler(), begin;
+  if (c == '}' || c == ':') {
+    handler();
+    return begin;
+  }
   if (c >= '0' && c <= '9') {
     int index = parse_nonnegative_int(begin, end, handler);
     if (begin == end || (*begin != '}' && *begin != ':'))
-      return handler.on_error("invalid format string"), begin;
-    handler(index);
+      handler.on_error("invalid format string");
+    else
+      handler(index);
+    return begin;
+  }
+  if (!is_name_start(c)) {
+    handler.on_error("invalid format string");
     return begin;
   }
-  if (!is_name_start(c))
-    return handler.on_error("invalid format string"), begin;
   auto it = begin;
   do {
     ++it;