[Python-ideas] Adding a thin wrapper class around the functions in stdlib.heapq

[bunslow]

Nothing so bombastic this time. The heapq functions are basically all named
"heapsomething", and basically all take a "heap" for their first argument,
with supplementary args coming after. It's a textbook example of the
(hypothetical) Object Oriented Manifesto™ where defining a class increases
type safety and programmers' conceptual clarity. There're practically no
drawbacks, and the code to be added would be very simple. Updating the
tests and docs would probably be harder.

In pure Python, such a class would look like this:

class Heap(list):

    def __init__(self, iterable=None):
        if iterable:
            super().__init__(iterable)
        else:
            super().__init__()

        self.heapify()

    push = heapq.heappush
    pop = heapq.heappop
    pushpop = heapq.heappushpop
    replace = heapq.heapreplace
    heapify = heapq.heapify

    # This could be a simple wrapper as well, but I had the following
thoughts anyways, so here they are
    def nsmallest(self, n, key=None):
        # heapq.nsmallest makes a *max* heap of the first n elements,
        # while we know that self is already a min heap, so we can
        # make the max heap construction faster
        self[:n] = reversed(self[:n])
        return heapq.nsmallest(n, self, key)

    # do we define nlargest on a minheap??


Wrapping around the C builtin functions (which aren't descriptors) would be
a bit harder, but not much so:

from functools import partial

class Heap(list):
    def __init__(self, iterable=None):
        if iterable:
            super().__init__(iterable)
        else:
            super().__init__()

        self.heapify = partial(heapq.heapify, self)
        self.push = partial(heapq.heappush, self)
        ...

        self.heapify()


Thoughts?
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