Condition Systems in an Exceptional Language - Chris Houser

There are some libraries for this. A great overview of the problem and some of the libs is [VIDEO] and a good set of corresponding notes at [LINK]

The stack unwinding was such a sad thing to me. Reading about CL condition system made me smile widely. You have more data to treat the exception. While reading the abstract, suddenly the word Exception felt absurd. It's rarely an exceptional condition, it's really a parallel planned error checking. Also, being from the Java era, an Exception was mostly a boring way to ensure error checking, while lispers did use exception as cut / tree jmp to provide solution values to an algorithm. ps: funny today youtube suggested this [VIDEO]

It turns out that it is, in fact, at least mostly possible to implement a condition type system in Clojure. See [VIDEO] I did a little bit of googling for Clojure libraries that do this: [LINK] and [LINK] I don't actually recommend any of these and haven't tried them. In particular I think using a non-standard library for your error handling, which is already probably relatively poorly tested, is probably a bad idea. I just wanted to point out that it's possible. I also think I remember something in a Rich Hickey talk (maybe "Clojure for Lisp Programmers"?) where someone in the audience asks about condition systems, and he responds that Clojure doesn't have one, but that it should be possible to build it.

You can do that yourself if you care ( [VIDEO] ) but I get what you mean. On the other hand, on a server application a REPL on exception wouldn’t help me.

True, the CL REPL is more useful than the Clojure REPL, but CL has a 20-30 year head start in development. Plus, Clojure was developed as a hosted language, and runs on .NET, Javascript, JVM, and even Dart (in-progress). Since exceptions are quite deeply integrated into those platforms (as opposed to conditions), it has "bled through" to the Clojure APIs, and, in turn, REPL. Folks have written a CL-style condition/restart library for Clojure ( [LINK] ) too. [VIDEO] video too.