Rhesus is an interpreter for the C-style Monkey toy programming language, built loosely according to Thorsten Ball’s book Writing an Interpreter in Go.

Why does this exist?

I’ve written compilers in Scala, but never in Go! Seemed like I ought to. (Well, I once wrote a YAML compiler in Go, but that was an accident.)

How is this different from the code included in the book?

I’m using the book’s code snippets as inspiration, especially in the beginning. If you’re reading the book, you should be able to tell what’s going on here.

Whereas the book code relies solely on Go’s core libraries, I’m vendoring dependencies where I see fit, e.g. stretcher/testify.

Is it finished?

Definitely not! I’m still working through Writing an Interpreter in Go and will continue with its sequel, Writing a Compiler in Go.

How can I help?

I’d be very surprised if anybody came here to ask this question, but if you’re interested, get in touch! I’m @jcmaunsell on Twitter. The more the merrier.


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