[Drup]

So, the TAPL ? :)

https://www.cis.upenn.edu/~bcpierce/tapl/

[catnaroek]

Not really. TAPL is a very useful book, but it won't teach you how to write a compiler, unless the only part of a compiler you actually care about is the type checker. The interpreters it describes (in the chapters titled “An ML implementation of <whatever>”) are ridiculously inefficient.

[Drup]

A good amount of new toy-ish languages compile to another language (typically javascript), and introduce new semantics and new type rules. As parent said, small DSLs.

You don't really need more than a typechecker and ast tranformations for that.

[nickpsecurity]

You have a link to a good guide for beginners on designing and efficiently implementing type checkers?

[catnaroek]

This is a nice introductory tutorial on how to implement Hindley-Milner type inference: https://github.com/jozefg/hm

This is a more advanced tutorial that illustrates a nice but tricky optimization that OCaml's type checker internally uses: http://okmij.org/ftp/ML/generalization.html

Finally, TAPL's type checkers are pretty good. They aren't designed for efficiency, though. They're designed to closely follow the book's contents: http://www.cis.upenn.edu/~bcpierce/tapl/checkers/

[nickpsecurity]

Thanks for the links!

[PaulHoule]

That's better than average if you are getting that as an undergrad!