FAQ
I've got an ordered list of MyClasses that I want to be able to do
binary searches on, but against a tuple. MyClass has valid
__lt__(self, rhs) and __eq__(self, rhs) member functions that work
when rhs is a tuple.

This works:
l = [MyClass(..), MyClass(..), ...]
l.find((a,b))

But this doesn't:
bisect.bisect(l, (a,b))

I'm assuming this is because inside bisect, it does 'key < list[x]'
rather than 'list[x] < key', so it's the tuple's __lt__ that is
called, rather than MyClass's tuple.

Is there a way around this? Can I monkeypatch a new __lt__ into the
tuple class?

Here's some sample code that demonstrates the problem (it uses ints
rather than tuples, but the

import bisect
class MyC:
def __init__(self, v):
self.v = v

def __lt__(self, rhs):
return self.v < rhs

# cant search for int in a list of MyC's
l = sorted([MyC(x) for x in range(1000)])
bisect.bisect(l, 40)
1001 # AKA not found

# but, I can search for MyC in a list of ints
l = sorted(range(1000))
bisect.bisect(l, MyC(40))
41

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grouppython-list @
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postedJun 17, '08 at 8:55p
activeJun 17, '08 at 11:36p
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