A small (yet Turing-equivalent) languageThe easiest programming language to implement is a minimalist, higher-order functional programming language known as the lambda calculus.
But, if you don't want to read those, I can convince you that there's more to the lambda calculus than you probably expected with just one program:((λ f . (f f)) (λ f . (f f)))This outwardly benign program is called Omega, and if you try to execute it, it doesn't terminate!
exp] [`(if ,ec ,et ,ef) (if (eval ec env) (eval et env) (eval ef env))] [`(letrec ,binds ,eb) (eval-letrec binds eb env)] [`(let ,binds ,eb) (eval-let binds eb env)] [`(lambda ,vs ,e) `(closure ,exp ,env)] [`(set!
(hash-ref env var) value)) ; ext…