//: A simple test harness. To create new tests, define functions starting with
//: 'test_'. To run all tests so defined, run:
//:   $ ./mu test
//:
//: Every layer should include tests, and can reach into previous layers.
//: However, it seems like a good idea never to reach into tests from previous
//: layers. Every test should be a contract that always passes as originally
//: written, regardless of any later layers. Avoid writing 'temporary' tests
//: that are only meant to work until some layer.

:(before "End Types")
typedef void (*test_fn)(void);
:(before "Globals")
// move a global ahead into types that we can&