Both "bound" (like, length known) and "unbound" (length unknown) are tested.
All of list, tuple, bytes, bytesarray offer approximately the same
performance, with "unbound" case being 30 times slower.
... and we have not that bad mapping type after all - lookup time is ~ the
same as in one-attr instance. My namedtuple implementation on the other
hand degrades awfully.
So, need to rework it. First observation is that named tuple fields are
accessed as attributes, so all names are interned at the program start.
Then, really should store field array as qstr[], and do quick 32/64 bit
scan thru it.
Motivation is optimizing handling of various constructs as well as
understanding which constructs are more efficient in MicroPython.
More info: http://forum.micropython.org/viewtopic.php?f=3&t=77
Results are wildly unexpected. For example, "optimization" of range
iteration into while loop makes it twice as slow. Generally, the more
bytecodes, the slower the code.
