more details added to CONTRIBUTING.md (#356)

Former-commit-id: 4d13b4f8ea42a4df48346c9600b169fa122ce1da

CONTRIBUTING.md

@@ -9,7 +9,7 @@ You will find here a summary of the different things you should do / look up to
     * HTTPS: `git clone https://github.com/<username>/Ark.git`
     * or SSH: `git clone [email protected]:<username>/Ark.git`
 * Create a branch for your feature: `git checkout -b feat/my-awesome-idea`
-* When you're done, push it to your fork and submit a pull request!
+* When you're done, push it to your fork and submit a pull request
 
 Don't know what to work on? No worries, we have a [list of things to do](https://github.com/ArkScript-lang/Ark/projects). Also, you can check the issues to find something to do!
 
@@ -21,7 +21,7 @@ Don't know what to work on? No worries, we have a [list of things to do](https:/
 * Conditions with a single statement (`if (condition) do_this();`) do not need to be enclosed in braces
 * Put a space between `for`, `while`, `if` and `(...)`, around each `=` sign (wherever it is, even in for-loops), between `#include` and the file to include
 * Prefer `enum class` over `enum`
-* Case
+* Naming:
     * Methods and functions: camelCase
     * Variables: snake_case
     * Constant expressions: PascalCase
@@ -47,9 +47,9 @@ for (std::size_t i = 0, end = container.size(); i < end; i++)
 ```
 * Header-guards should be written using `#ifndef`, `#define` and `#endif`, the define being in MACRO_CASE
 * Functions and methods which can not throw exceptions must be marked `noexcept`
-* In header files, have a blank line between each method / function / structure / constant ; also put blanks line around includes blocks
+* In header files, have a blank line between each method / function / structure / constant ; also put blank lines around include blocks
 * In classes, avoid using `this`. Prefix every member variable with `m_`
-* In classes, do not declare the methods in the header file, only in the source file (unless they are `inline` or templated)
+* In classes, do not define the methods in the header file, only in the source file (unless they are `inline` or templated)
 * Add Doxygen file comments at the top of each newly created header file:
 ```cpp
 /**
@@ -81,10 +81,10 @@ Snippet to recapitulate guidelines for headers:
  * @copyright Copyright (c) 2020
  * 
  */
- 
+
 #ifndef HEADER_GUARD
 #define HEADER_GUARD
- 
+
 #include <Ark/Compiler/Something.hpp>
 #include <vector>
 
@@ -102,19 +102,37 @@ namespace Ark
          * 
          */
         Lexer();
-        
+
         /**
          * @brief doxygen documentation here
          * 
          */
         void aMethod();
-        
+
     private:
         int m_member;  ///< This is a doxygen comment
     };
 }
 
-#endif
+#endif  // Adding an empty line at the end of each file is strongly advised
+
+```
+
+### Checking the enforcement of the coding style
+
+It is strongly advised to run clang-format on your code *before* submitting a pull request.
+
+You can do as follows if you are a Windows user:
+```powershell
+Function run-on {
+    param (
+        $folder
+    )
+    Get-ChildItem -Path $folder -File -Recurse | Foreach {clang-format -style=file -i $_.fullname}
+}
+
+run-on .\include\Ark
+run-on .\src
 ```
 
 ## ArkScript coding guidelines