Comment by cosmos0072

The core idea is simple: do a type analysis on each expression you want to "compile" to a closure, and instantiate the correct closure for each type combination.

Here is a pseudocode example, adapted from gomacro sources:

https://gist.github.com/cosmos72/f971c172e71d08030f92a1fc5fa...

This works best for "compiling" statically typed languages, and while much faster than an AST interpreter, the "tree of closures" above is still ~10 times slower that natively compiled code. And it's usually also slower than JIT-compiled code