the original set language, SETL, was invented as a DSL for compiler optimizations. Compiler backends heavily use set operations, and SETL made them efficient &

the original set language, SETL, was invented as a DSL for compiler optimizations. Compiler backends heavily use set operations, and SETL made them efficient & succinct. In fact, the original SETL compiler itself was highly optimizing and benefited greatly from the new "executable notation".