<i>They are not what Lisp macros do.</i><p>True.<p><i>What ruby does to present micro-DSLs are what any language that lets the programmer influence the scope of single dispatch and has a lightweight syntax for function calls can do.<p>They are not what Lisp macros do, and do not even approach all the common "easy" uses cases for macros. Further, they also incur a much larger runtime performance penalty, whereas macros incur none.</i><p>I think that part of the problem is that no one (whom I've seen, at least) has explained in a brief, easy to follow manner just what the Lisp macros get you beyond all of the parse tree manipulation, code generation, and "metaprogramming" you can already do with Ruby.  If you could explain the extra benefit succinctly, I'd love to hear it.  In other words, I'd love to see an essay or blog post that makes me <i>wish</i> Ruby had true, Lisp-style macros.<p>Performance, by the way, won't be enough: language implementations are always getting better.