If you’re thinking of writing a language in earnest, you will create something much more valuable if you start from a novel semantics, and only then come up with a syntax to express those semantics, than if you were to start from syntax.

The world does not need yet another reskin of Java, but it could use new programming paradigms and new ways of solving problems.

As a learning exercise, implementing a language is worthwhile simply to gain the understanding that languages are not magic. To boot, you’ll pick up loads of useful techniques in the realms of parsing, data flow analysis, error reporting, and optimisation.

Indeed. Recently I was inspired to learn K, a language in the APL family. There aren't many implementations available, so I wrote my own. Doing this forced me to come to terms with a whole range of features I might have otherwise shied away from using.

Hi! Is your implementation available for use?

I'm curious - how did you test it for compatibility with the main K implementation?

I don't have a rigorous approach for testing compatibility at present; My starting point was the K2 manual, and I've tried to get as many examples from that working as possible. I have been learning the language as I go, so often I don't realize functionality is missing until I stumble across an existing K program that doesn't work properly.

I'm targeting K5, which is unreleased, so there's a great deal of speculation. I think I have a decent subset of the functionality working now, but most of the time when I write new programs using it I still shake out bugs and unhandled edge cases.