miniblog.

Today I learnt that Racket *intentionally* doesn't have a traditional REPL workflow. The authors were concerned about students not understanding the state between the current session and the code on disk. (Arguably Jupyter has some of these features now.)

I'm designing a programming language and trying to decide the type of `let x = 1;`. Should it be Unit or Int? Advantage of Int: really convenient when evaluating snippets in a REPL. Advantage of Unit: It's much less confusing when type inference runs on an incomplete function.

tap> is an elegant Clojure debugging feature: it passes the argument to any functions registered with add-tap. You might set up a custom printer for your data type, or save values for later examination, and you can easily disable the tap too.