Update readme
diff --git a/README.rst b/README.rst
index fecbf5f..05cc452 100644
--- a/README.rst
+++ b/README.rst
@@ -76,6 +76,28 @@
std::string s = fmt::format("{0}{1}{0}", "abra", "cad");
// s == "abracadabra"
+Format strings can be checked at compile time:
+
+.. code:: c++
+
+ // test.cc
+ using namespace fmt::literals;
+ std::string s = "{2}"_format(42);
+
+.. code::
+
+ $ g++ -Iinclude test.cc -std=c++14
+ ...
+ test.cc:5:31: note: in instantiation of function template specialization
+ 'fmt::internal::udl_formatter<char, '{', '2', '}'>::operator()<int>' requested
+ here
+ std::string s = "{2}"_format(42);
+ ^
+ include/fmt/format.h:3838:7: note: non-constexpr function 'on_error' cannot be
+ used in a constant expression
+ on_error("argument index out of range");
+ ^
+
fmt can be used as a safe portable replacement for ``itoa``:
.. code:: c++