fact: Definition dispatch (x p : E) '(ys, zs) A (f : seq E -> seq E -> M A) : M A := if x <= p then qperm zs >>= f (rcons ys x) else qperm (rcons zs x) >>= f ys.
imports: mathcomp(all_ssreflect) monae_lib hierarchy monad_lib fail_lib state_lib array_lib example_quicksort infotheo(ssr_ext)