Attached find a unified diff that upgrades the bisect module in two
important ways:
1. bisect and friends now understand cmp, key, and reverse, the same way
that list.sort does.
2. bisect and insort now have parameterized handedness: instead of using
two different functions depending on whether you want new items to show
up before or after existing ones, bisect and insort now take a flag
called 'right' which can change the handedness on the fly.
Currently this code fails two existing regression tests:
test_backcompatibility, because bisect is no longer the same as
bisect_right; and test_non_sequence, because insort now raises
AttributeError instead of TypeError when called on an int.
Still to do, in order of priority as perceived by me:
1. A C version of the code needs to be written.
2. The error handling should be worked over by somebody with more
knowledge than I - the regression tests assume that particular failures
(len-only, get-only, and non-sequence) will happen with one of TypeError
or AttributeError when in reality they may raise the other.
3. The tests for new functionality should be made more exhaustive.
4. The in-module documentation probably needs cleaning; the rst
documentation needs my name added to it (a good deal of the existing
writing is still Fred L Drake's, so I won't replace) and needs to have
the "section 3.6.4" part linked to Mutable Sequence Types; I couldn't
find an actual example of that linkage.
5. The godawful conditions in bisect should probably get cleaned up.