Why Macros?

Clojure stands on the shoulders of giants, with influences from several functional and object-oriented languages, database and distributed systems technologies, and of course the tremendous force of nature that is its creator, Rich Hickey. And despite Clojure’s youth, we’ve already started to see some cross-pollination into other language communities. But one of the real killer features of Clojure is the macro system, which is similar in many ways to Common Lisp’s but brings its own modern flair to the area.

Macros in Clojure are an elegant metaprogramming system, a means to accomplish goals that might seem impossible in other languages. How hard would it be to add pattern matching or a new control flow structure to your language as a library (rather than patching the core language)? In Clojure, people like you and me have the power to do these things ourselves.

It’s true in a sense that all general-purpose languages are equally powerful, but we programmers know better. Our limitations and goals are not the same as those of a Turing machine. We want lean, clean code that expresses our intent clearly while allowing us to tell the machine what to do as succinctly as possible. Macros are a way to get there.