Introduction to metaprogramming

Metaprogramming refers to writing a computer program, writing or manipulating other programs (or themselves) as their data, or completing some work that should be completed at compile time at run time. In many cases, this is more efficient than writing all the code by hand. The language in which the metaprogram is written is called the metalanguage, and the language in which the metaprogram is run is called the target language. The ability of a language to become its own metalanguage is called reflection.