Mastering Python Design Patterns - Second Edition

Real-world examples

The daily routine of a worker, especially for workers of the same company, is very close to the Template design pattern. All workers follow more or less the same routine, but specific parts of the routine are very different.

In software, Python uses the Template pattern in the cmd module, which is used to build line-oriented command interpreters. Specifically, cmd.Cmd.cmdloop() implements an algorithm that reads input commands continuously and dispatches them to action methods. What is done before the loop, after the loop, and at the command parsing part are always the same. This is also called the invariant part of an algorithm. What changes are the actual action methods (the variant part) [j.mp/templatemart, page 27]. ...