C4 – C in 4 functions

On a first skim, this looks really nice; complaints that it's unreadable are unfounded. The background that makes it readable are Wirth's Compiler Construction http://www.ethoberon.ethz.ch/WirthPubl/CBEAll.pdf plus precedence climbing http://en.wikipedia.org/wiki/Operator-precedence_parser#Prec...

It is unreadable. Lumping code together into big functions just so you can say "Look I've created a compiler in 4 functions" is pointless, unless your goal is to post it to HN to show everyone how clever you are.

This is not how you code when you work in a team or when you know some other poor soul has to come along and maintain it.

I suggest you take a look at [1] then go and read this excellent book by Martin Fowler: "Refactoring: Improving the Design of Existing Code" [2]

[1] https://en.wikipedia.org/wiki/Code_smell

[2] http://www.goodreads.com/book/show/44936.Refactoring