[PATCH 7 of 9 RFC] revset: added order property to lazyset classes

[Matt Mackall]

On Wed, 2014-02-12 at 14:39 -0800, Lucas Moscovicz wrote:
> # HG changeset patch
> # User Lucas Moscovicz <lmoscovicz at fb.com>
> # Date 1391791458 28800
> #      Fri Feb 07 08:44:18 2014 -0800
> # Node ID 35e93209ef29f786911232f9f37ad95661abf3d9
> # Parent  1cc650bf69c051609ef85d955d7562cbf9285743
> revset: added order property to lazyset classes

This looks promising. Using strings for the direction names is a bit
unfortunate though.

Perhaps we can do something like this:

def ascending(self):
    # true if we can -efficiently- traverse this set in ascending order

def descending(self):
    # true if we can -efficiently- traverse this set in descending order

Both of these would be true for lazyset and spanset. And then we can
make algorithms that are conditional on these.

-- 
Mathematics is the supreme nostalgia of our time.