After this change, I'm still not quite sure what your code is trying to do (I haven't clicked your links yet), so I'll try some example cases:

  arc> (mktransition '(1 2 3 4 5))
  (1 (5 (cdr str)))
  
  arc> (mktransitions '((2 3) (4 5)))
  (
    2 (3 (cdr str))
    4 (5 (cdr str)))
  
  arc> (mkrule '(1 (2 3) (4 5)))
  (list (car (1 (2 3) (4 5)))
        (fn (str)
          (if (empty str)
            t
            (case (car str)
              2 (3 (cdr str))
              4 (5 (cdr str))))))

Since you end up with function calls like (3 (cdr str)), it looks like you're trying to make several functions under the same scope (using Anarki's 'withr/p), and it looks like 'str is a variable that contains the remaining inputs of the automaton.

In this case, I recommend changing `(list (cdr ,i) (fn ...)) so that it's (list (cdr i) `(fn ...)), since you probably didn't want that 'list symbol in the 'withr/p call.

To make this easy to test, here's the complete code, with Anarki's definition of 'withr/p and my updates to 'mkrule:

  ; a 'with that works for defining recursive fns
  (mac withr/p (bindings . body)
    " Scheme's 'letrec.
      See also [[withr]] [[where]] "
    `(let ,(map1 car bindings) nil
       ,@(map [cons 'assign _] bindings)
       ,@body))
  
  (def mktransition (tn) (list (car tn) (list (last tn) '(cdr str))))
  
  (def mktransitions (ts)
    (accum accfn
      (each x (map1 mktransition ts)
        (accfn (car x))
        (accfn (last x)))))
  
  (def mkrule (r)
    (let i r
      (list (car i) `(fn (str)
                        (if (empty str) t
                          (case (car str)
                            ,@(mktransitions (cdr i))))))))
  
  (mac automaton (i r) `(withr/p ,(map1 [mkrule _] r) ,i))

  (= matches-aabb
    (automaton step-a
      (
        (step-a
          (a step-a)
          (b step-b))
        (step-b
          (b step-b)))))
  
  arc> (matches-aabb '(a a a a b b b b))
  t
  arc> (matches-aabb '(a a a a b b b b a))
  nil
  arc> (matches-aabb '(a a a a))
  t
  arc> (matches-aabb '(b b))
  t
  arc> (matches-aabb '())
  t
  arc> (matches-aabb '(b a))
  nil
  arc> (matches-aabb '(c))
  nil

  ; example call:
  ; (automaton 'init
  ;            '((init (c more))
  ;              (more (a more)
  ;                    (d more)
  ;                    (r end))
  ;              (end)))

  -(mac automaton (i r) `(withr/p ,(map1 [mkrule _] r) ,i))
  +(def automaton (i r) (eval `(withr/p ,(map1 [mkrule _] r) ,i)))

Did you mean in some other language? It's easy to build a test harness, it's usually the first thing I do with a new language, and invariably just a few lines of code.

Here's my test harness in C++, for example: https://github.com/akkartik/wart/blob/cc70d66ee6/literate/00.... Even in C++ it's just 50 lines or so. Dynamic languages are often even shorter.

(It's not a normal C++ project. I use readable diff directives inside :(..) to add the test harness to the skeleton program at https://github.com/akkartik/wart/blob/cc70d66ee6/literate/00.... But now that this is done, any function I write with 'test_' is automatically run in test mode. Look at the makefile to see how I do that with minimal code.)

I actually applied with it for Lisp In Summer Projects (http://lispinsummerprojects.org/), which is why I haven't announced it -- you're supposed to do the work yourself, without help. And people here like to help out and post code. :-p

The oauth utility is also for the LISP contest -- we'll see how far I get over the next few weeks.

Either way I'm planning on uploading a few bits and pieces to Anarki or my own repos over the next couple of weeks. (spent some time on anarki's web.arc, the state machine stuff, oauth, some lazy evaluation stuff, etc...)

Please let me know what you think -- email in profile, comment here, open bitbucket tickets, find me on the street^1, etc.

So I'll just explain what, in my mind, is the biggest difference -- how I want to use it. To run the anarki test-iso test, you execute the entire `(test-iso ..)` sexp. If you want to run a bunch of tests, you have to execute all the sexps.

That's kind of a hassle. Especially if you find a bug, have a bunch of tests that fail, then change a small thing in the function, and want to re-run all the tests.

In my unit-test.arc, all you have to do is call `(run-suites suite-name)`, and it'll run as many tests as you've got in `suite-name`. You don't have to copy a bunch of sexps into the repl or reload the file (and what if you want to run a subset of a file? You can't). Also -- and this is one of the features I'm currently working on (https://bitbucket.org/zck/unit-test.arc/issue/21/after-runni...), what if you run one hundred tests at once? Do you really want to parse -- with your eyes, like a bloody scribe -- every single line of output to find the seven tests that broke? And when you then make a fix, you're not going to want to parse them again, so you'll only run the seven that failed before. So if you broke something else, you won't find that out.

So, what falls out of my desire to run a set of tests easily and repeatably, and have summarized output? Some sort of grouping, with a single point of entry to run the tests -- that is to say, test suites.