-updated README.md

README.md

@@ -1,12 +1,38 @@
 ## sfun
+
 [![build & test (clang, gcc, MSVC)](https://github.com/kamchatka-volcano/sfun/actions/workflows/build_and_test.yml/badge.svg?branch=master)](https://github.com/kamchatka-volcano/sfun/actions/workflows/build_and_test.yml)
 
-**sfun** - is a small header-only library for utility functions that are so small and simple that you define them near the caller and forget to test them.
+**sfun** - is a header-only collection of utilities for string manipulation, metaprogramming, core guidelines support
+and other general-purpose tasks.
+
+### Contents
 
+* `contract.h` - Macros for contract programming, violations lead to `std::terminate()` (the implementation is copied
+  from [GSL](https://github.com/microsoft/GSL))
+* `functional.h` - Metaprogramming and other helpers for functions and callable objects;
+* `interface.h` - `sfun::interface`, a private base class that brings the properties for virtual interfaces recommended
+  by Core Guidelines (non-copyable, non-movable, has virtual destructor); `sfun::access_permission` - a restricted
+  member access alternative to the `friend` keyword, based on
+  the [badge pattern](https://awesomekling.github.io/Serenity-C++-patterns-The-Badge/) idea.
+* `member.h` - A wrapper that allows storing const and reference types members without affecting the parent class's copy
+  and move properties (as recommended by Core Guidelines).
+* `optional_ref.h` - A non-rebindable optional reference wrapper implementation.
+* `path.h` - Helpers to follow [ut8everywhere manifesto](https://utf8everywhere.org) by storing UTF-16
+  inside `std::filesystem::path` on Windows and UTF-8 on other platforms. All `std::filesystem::path` objects should be
+  constructed with `sfun::make_path` and converted to a string with `sfun::path_string`.
+* `precondition.h` - Precondition wrappers for function arguments, based on the idea of
+  the [`precond`](https://github.com/denniskb/precond) library.
+* `string_utils.h` - Basic string utils based on STL algorithms.
+* `type_list.h` - A basic type list for metaprogramming.
+* `type_traits.h` - A collection of type traits.
+* `utility.h` - Miscellaneous helpers, some are from the standard library newer than C++17.
+* `wstringconv.h` - UTF-16 to UTF-8 string conversion for Windows, provided by
+  the [`utfcpp`](https://github.com/nemtrif/utfcpp) library bundled in the `detail/` directory.
 
 ### Installation
 
 Download and link the library from your project's CMakeLists.txt:
+
 ```
 cmake_minimum_required(VERSION 3.14)
 
@@ -25,7 +51,7 @@ add_executable(${PROJECT_NAME})
 target_link_libraries(${PROJECT_NAME} PRIVATE sfun::sfun)
 ```
 
-For the system-wide installation use these commands:
+To install the library system-wide, use the following commands:
 ```
 git clone https://github.com/kamchatka-volcano/sfun.git
 cd sfun
@@ -34,7 +60,8 @@ cmake --build build
 cmake --install build
 ```
 
-Afterwards, you can use find_package() command to make installed library available inside your project:
+After installation, you can use the `find_package()` command to make the installed library available inside your
+project:
 ```
 find_package(sfun 1.0 REQUIRED)
 target_link_libraries(${PROJECT_NAME} PRIVATE sfun::sfun)