Unit tests

test-async

Macro. Example:

(test-async (dex-string/nil)
  (fn out
    (string-append-later str.\;qq[Hello,\s] str.\;qq[world!] /fn str
    /definer-define out (dex-give-up/nil) str))
  (fn out
    (definer-define out (dex-give-up/nil) str.\;qq[Hello, world!])))

Todo

Document this.