C++11 - User-defined literals

C++11 standard provides new way of customized literal constants called user defined literals. Thanks to that user can define own suffixes for standard literals (ex. digits) which defines it better and makes it better readable. Example of such suffixes could be: _meters, _kilograms, _squareMeters etc.

For better understanding user-defined literals concept, let's take a look on the below example code: Output of that code is: In point one we can see concept of operator overloading function which should be used in order to define user-defined literals. In our example we are defining suffixex _meters and _squareMeters which will be used for imporve readability of code of calculations based on that units.

Point II shows how we can use user-defined literals to assign values to variables. Such usage definitely makes code better readable and easier to understand.

Point III, shows how we can use other suffix (_squareMeters) in comparison calculations. As we can see, our units are logically used the same way as normal number literals. However, (thanks to user-defined literals) we can easely understand which units are used in particular case.

Points III and IV, shows how user-defined literals are used in printing its values into console. We can see that values printed from our literals are the same as its numerical values.

Code of above example can be found on our github account: https://github.com/xmementoit/CppAdventureExamples/tree/master/cpp11/userDefinedLiterals

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