Scala's DSLs are internal DSLs, made through the use of higher order functions, closures and implicit conversions. That's very different from external DSLs, wri

Scala's DSLs are internal DSLs, made through the use of higher order functions, closures and implicit conversions. That's very different from external DSLs, written in a separate language (macros in C and C++). There are also DSLs that straddle the line e.g., C++ templates ("generic meta programming") and Lisp macros (application of Lisp but at a different stage, resulting in new s-exps). That's a big distinction.