On my way to learn Lisp I have discovered the all powerful and feared so called Macros, then after spending a hard time trying to understand them and their usefulness I said to myself, I FINALLY GOT IT.
I couldn’t be more wrong, I was thinking that the only purpose of Macros was to define new control structures and that was all I needed to know until I start reading more and more on the subject and a whole new world has comes to me !
One can use Macros for new Domain Specific Language, Code Transformation and to avoid Boilerplate Code.
Hence, if a few examples at which the aforementioned usages of macros and others as well, with a concise and simple-to-understand explanation could be given it would be really nice.
The canonical reference for LISP macros is
On Lisp: Advanced Techniques for Common Lisp, by Paul Graham (book version). It is out of print, and everyone who owns a copy knows what it is worth. You can
download it, but Paul says nine figures got lost somewhere in the ozone.
Let Over Lambda, by Doug Hoyte, is also good.