//: Run multiple routines concurrently, without any guarantees on how the
//: operations in each are interleaved with each other.

:(before "End Globals")
size_t Scheduling_interval = 500;

//: first, add a deadline to run()
//: todo: these changes are ugly and brittle
:(replace{} "void run(recipe_number r)")
void run(recipe_number r) {
  run(routine(r), Scheduling_interval);
}
:(replace "void run(routine rr)")
void run(routine rr, size_t time_slice)
:(replace "while (!done(rr))" following "void run(routine rr, size_t time_slice)")
size_t ninstrs = 0;
while (!done(rr) && ninstrs < time_slice)
:(after "Running One Instruction")
ninstrs++;