[mbrodersen]

Advanced type systems are fun to play with. But unfortunately some people get carried away and build a mountain of unnecessary complexity that other developers then have to deal with. A bit like Lisp macros. It is fun to implement your own type system and DSLs in Lisp. But the result is likely to be completely unmaintainable by anybody else and yourself a year later when you have forgotten how it works. I have seen the same happen with templates in C++. Developers that spend weeks having fun building a mountain of template hell to solve a problem that could have been solved in a few hours without template magic. As with everything else, keeping an eye on the benefit/cost ratio is key.

[lispm]

I'd expect Lisp macros to be easier to debug, since they are written in Lisp themselves (and not in a template language) and the usual interactive debugging tools apply.

There are lots of Lisp DSLs using macros which have been maintained by different people over several decades.