The key idea of generic programming with templates is it to define functions and classes which
can be used with various types. Often it happens that you instantiate a template with the wrong
type. The result is typically a few pages of cryptic error messages. This sad story ends with
concepts. Concepts empower you to write requirements for your templates which can be
checked by the compiler. Concepts revolutionise the way, we think about and write generic
code. Here is why:
However, this is not the end of the story.